Image sensor module

ABSTRACT

An image sensor module includes a light source unit that emits a linear light beam elongate in a primary scanning direction to an object to be read, and a lens unit including an incidence surface and an output surface oriented opposite to each other. The lens unit is configured to receive light from the object through the incidence surface and output the light through the output surface. The module also includes a sensor IC that receives the light outputted from the output surface, a housing that holds the light source unit and the lens unit, and a support member that supports the lens unit such that the incidence surface is located more distant from the sensor IC than the output surface in a secondary scanning direction. The support member includes a reflection surface that reflects the light from the object toward the incidence surface.

TECHNICAL FIELD

The present invention relates to an image sensor module used for examplein a document scanner.

BACKGROUND ART

FIG. 38 illustrates an example of conventional image sensor modules. Theimage sensor module 900 shown in FIG. 38 serves to read a writtencontent of an object to be read 890 transported in a secondary scanningdirection y, as image data. The image sensor module 900 includes ahousing 91, a substrate 92, an LED module 93, a light guide 94, a lensunit 95, a sensor IC 96, and a transmission plate 97. The housing 91 hasan elongate shape extending in a primary scanning direction orthogonalto the secondary scanning direction y and a thickness direction z. Thesubstrate 92 has an elongate rectangular shape extending in the primaryscanning direction, and is fitted in the housing 91. The LED module 93includes a plurality of LED chips 93 a, and is located close to an endportion of the housing 91 in the primary scanning direction.

The light guide 94 serves to emit the light from the LED module 93toward the object to be read 890, and is formed of a transparent resinmaterial. The light guide 94 has an elongate shape extending in theprimary scanning direction, and includes an incidence surface (notshown), a reflection surface 94 a, and an output surface 94 b. Theincidence surface is an end face of the light guide 94 in the primaryscanning direction and configured to face the LED chips 93 a. Thereflection surface 94 a serves to reflect the light from the incidencesurface. The output surface 94 b has an elongate shape extending in theprimary scanning direction, and serves to output the light that hasproceeded through inside the light guide 94 to the object to be read890, in a form of a linear light beam extending in the primary scanningdirection. The light outputted from the light guide 94 is emitted to theobject to be read 890 through the transmission plate 97, and reflectedby the object to be read 890. The reflected light is converged into thesensor IC 96 by the lens unit 95. The sensor IC 96 is capable ofoutputting a signal based on the amount of received light. The writtencontent of the object to be read 890 can be read as an image, by storingthe signals from the sensor IC 96 in a non-illustrated memory.

When the object to be read 890 is creased or wrinkled, the object to beread 890 is prone to be lifted from the transmission plate 97. To form aclear image of the written content of the object to be read 890 in thesensor IC 96 under such a condition, it is advantageous to prolong theoptical path between the object to be read 890 and the sensor IC 96.However, locating the sensor IC 96 at a lower position in order toprolong the optical path results in an increase in size of the imagesensor module 900 in a thickness direction z. Such an increase in sizemakes it difficult to properly incorporate the image sensor module 900in a related device, such as a document scanner.

Accordingly, the optical path length may be prolonged by placing areflecting mirror in the housing 91 thereby bending the optical path. Bybending optical path, the optical path can be prolonged by moving thesensor IC 96 in a horizontal direction, instead of moving the sensor IC96 to a lower position. Therefore, the housing 91 can be formed with areduced thickness. In this case, however, a cavity has to be providedinside the housing 91 for allowing the light to pass, which leads to adecline in rigidity of the housing 91, even though the housing 91 can bemade thinner.

DOCUMENT LIST Patent Document

-   -   Document 1: Japanese Patent Publication No. 2007-300536

SUMMARY OF INVENTION Technical Problem

The present invention has been proposed in view of the foregoingsituation. An object of the present invention is to provide a thin imagesensor module without compromising the rigidity.

Solution to Problem

According to a first aspect of the present invention, there is providedan image sensor module including: a light source unit that emits alinear light beam elongate in a primary scanning direction to an objectto be read; a lens unit including an incidence surface and an outputsurface oriented opposite to each other, the lens unit being configuredto receive light from the object through the incidence surface andoutput the light through the output surface; a sensor IC that receivesthe light outputted from the output surface; a housing that holds thelight source unit and the lens unit; and a support member that supportsthe lens unit such that the incidence surface is located more distantfrom the sensor IC than the output surface in a secondary scanningdirection. The support member includes a primary reflection surface thatreflects the light from the object toward the incidence surface.

In a preferred embodiment, the reflection surface is located so as tooverlap the lens unit as viewed in the secondary scanning direction.

In a preferred embodiment, the lens unit is supported such that anoptical axis of the lens unit is aligned with the secondary scanningdirection.

In a preferred embodiment, the support member includes a bottom faceperpendicular to a thickness direction orthogonal to both of the primaryscanning direction and the secondary scanning direction, and the housingincludes a support region provided with a support surface held incontact with the bottom face.

In a preferred embodiment, the support member includes: a transmissiveportion provided with a primary sloped surface inclined so as to becloser to the light source unit in the secondary scanning direction asproceeding away from the bottom face in the thickness direction; and anon-transmissive layer formed so as to cover the sloped surface; and thereflection surface is located at an interface between the transmissiveportion and the non-transmissive layer.

In a preferred embodiment, the transmissive portion is formed integrallywith the lens unit so as to cover the lens unit.

In a preferred embodiment, the housing includes an elevated portionprotruding in the thickness direction from the support surface, and theelevated portion is in contact with the non-transmissive layer.

In a preferred embodiment, the support region includes a groovepenetrating therethrough in the thickness direction, the groove beingformed at a position overlapping the sensor IC as viewed in thethickness direction, and the support member includes an additionalreflection surface formed so as to overlap the sensor IC as viewed inthe thickness direction.

In a more preferred embodiment, the transmissive portion includes: anadditional sloped surface formed opposite to the primary sloped surfacein the secondary scanning direction and inclined so as to be closer tothe light source unit as proceeding away from the bottom face in thethickness direction; and an additional non-transmissive layer formed soas to cover the additional sloped surface, and the additional reflectionsurface is located at the interface between the additional slopedsurface and the additional non-transmissive layer.

In a preferred embodiment, the housing has a thickness directionorthogonal to both of the primary scanning direction and the secondaryscanning direction, the housing supporting the support member. Thesupport member includes a bottom face held in contact with the housingand a primary upright surface erected from the bottom face and extendingin the primary scanning direction. The reflection surface is inclinedwith respect to the upright surface.

In a preferred embodiment, the upright surface is in contact with thehousing.

In a preferred embodiment, the support member includes an additionalupright surface erected from the bottom face and extending in theprimary scanning direction, and the additional upright surface islocated opposite to the primary upright surface across the lens unit inthe secondary scanning direction.

In a preferred embodiment, the support member includes a recessedportion extending in the primary scanning direction and recessed awayfrom the sensor IC, and the housing includes a pair of wall portionsextending in the primary scanning direction and fitted in the recessedportion, and a slit formed between the pair of wall portions and facingthe sensor IC.

Preferably, the slit includes a pair of primary sloped surfacesextending in the primary scanning direction and inclined so as to bemore distant from each other in the secondary scanning direction asproceeding toward the sensor IC in a thickness direction orthogonal toboth of the primary scanning direction and the secondary scanningdirection.

Preferably, the slit includes a pair of additional sloped surfacesextending in the primary scanning direction and inclined so as to becloser to each other in the secondary scanning direction as proceedingtoward the sensor IC in the thickness direction orthogonal to both ofthe primary scanning direction and the secondary scanning direction, andthe pair of additional sloped surfaces is located more distant from thesensor IC than the pair of primary sloped surfaces in the thicknessdirection.

Preferably, the slit includes a pair of horizontal surfaces extending inthe primary scanning direction and perpendicular to the thicknessdirection, and each of the horizontal surfaces is located between one ofthe pair of primary sloped surfaces and one of the pair of additionalsloped surfaces.

In a preferred embodiment, the sensor IC includes a photodetectingsurface perpendicular to the thickness direction, and the pair ofhorizontal surfaces is oriented in a same direction as thephotodetecting surface.

In a preferred embodiment, the sensor IC includes a photodetectingsurface perpendicular to the thickness direction, and the pair ofhorizontal surfaces is configured to face the photodetecting surface.

In a preferred embodiment of the present invention, the housing includesa slit facing the sensor IC, and the support member includes aprojecting portion extending into the slit.

In a preferred embodiment of the present invention, the image sensormodule further includes a sensor IC support base supporting the sensorIC and fixed to the support member.

Preferably, the support member includes a recessed portion in which thesensor IC is placed.

Preferably, an anti-reflection member is provided inside the recessedportion.

In a preferred embodiment, the support member includes an additionalreflection surface that reflects the light from the output surface, andthe lens unit is located between the primary reflection surface and theadditional reflection surface in the secondary scanning direction.

In a more preferred embodiment of the present invention, a lightshielding member is provide for covering the support member in a mannersuch that at least the reflection surface is exposed.

Preferably, the housing has a thickness direction orthogonal to both ofthe primary scanning direction and the secondary scanning direction andsupports the support member, the support member includes a bottom facesupported by the housing and a primary sloped surface inclined withrespect to the bottom face, the light shielding member includes a slopedsurface anti-reflection portion held in close contact with a part of thesloped surface, and the reflection surface is a portion uncovered withthe sloped surface anti-reflection portion of the sloped surface and aninterface with air.

Preferably, the light shielding member includes a bottom faceanti-reflection portion held in close contact with the bottom face.

Preferably, the support member includes a top face opposite to thebottom face in the thickness direction, and the light shielding memberincludes a top face cover portion that covers the top face.

Preferably, the support member includes an additional sloped surfaceinclined with respect to the bottom face, the lens unit is locatedbetween the primary sloped surface and the additional sloped surface inthe secondary scanning direction, and the light shielding memberincludes an additional sloped surface anti-reflection portion disposedin close contact with a part of the additional sloped surface.

According to a second aspect of the present invention, there is providedan image sensor module including: a light source unit that emits alinear light beam elongate in a primary scanning direction to an objectto be read; a lens unit including an incidence surface and an outputsurface oriented opposite to each other and configured to receive lightfrom the object through the incidence surface and output the lightthrough the output surface; a sensor IC that receives the lightoutputted from the output surface; a housing that holds the light sourceunit and the lens unit; and a support member that supports the lens unitsuch that the incidence surface is located more distant from the sensorIC than the output surface in a secondary scanning direction. Thesupport member includes a reflection surface that reflects the lightfrom the object toward the sensor IC.

In a preferred embodiment, the reflection surface is located so as tooverlap the lens unit as viewed in the secondary scanning direction.

In a preferred embodiment, the lens unit is supported such that anoptical axis of the lens unit is aligned with the secondary scanningdirection.

In a preferred embodiment, the support member includes a bottom faceperpendicular to a thickness direction orthogonal to both of the primaryscanning direction and the secondary scanning direction, and the housingincludes a support region provided with a support surface held incontact with the bottom face.

In a preferred embodiment, the support region includes a groovepenetrating therethrough in the thickness direction, the groove beingformed at a position overlapping the sensor IC as viewed in thethickness direction, and the reflection surface is located so as tooverlap the groove as viewed in the thickness direction.

In a preferred embodiment, the support member includes a transmissiveportion provided with a primary sloped surface inclined so as to becloser to the light source unit in the secondary scanning direction asproceeding away from the bottom face in the thickness direction, and anon-transmissive layer formed so as to cover the sloped surface, and thereflection surface is located at an interface between the transmissiveportion and the non-transmissive layer.

In a preferred embodiment, the transmissive portion is formed integrallywith the lens unit so as to cover the lens unit.

In a more preferred embodiment, an additional reflection surface isprovided for reflecting the light from the object toward the incidencesurface.

More preferably, the transmissive portion includes: an additional slopedsurface formed opposite to the primary sloped surface in the secondaryscanning direction and inclined so as to be closer to the light sourceunit as proceeding away from the bottom face in the thickness direction;and an additional non-transmissive layer formed so as to cover theadditional sloped surface, and the additional reflection surface islocated at the interface between the additional sloped surface and theadditional non-transmissive layer.

More preferably, the housing includes an elevated portion protruding inthe thickness direction from the support surface, and the elevatedportion is in contact with the additional non-transmissive layer.

In a preferred embodiment of the present invention, the support memberincludes a recessed portion extending in the primary scanning directionand recessed away from the sensor IC, and the housing includes a pair ofwall portions extending in the primary scanning direction and fitted inthe recessed portion, and a slit formed between the pair of wallportions and facing the sensor IC.

Preferably, the slit includes a pair of primary sloped surfacesextending in the primary scanning direction and inclined so as to bemore distant from each other in the secondary scanning direction asproceeding toward the sensor IC in the thickness direction orthogonal toboth of the primary scanning direction and the secondary scanningdirection.

Preferably, the slit includes a pair of additional sloped surfacesextending in the primary scanning direction and inclined so as to becloser to each other in the secondary scanning direction as proceedingtoward the sensor IC in the thickness direction orthogonal to both ofthe primary scanning direction and the secondary scanning direction, andthe pair of additional sloped surfaces is located more distant from thesensor IC than the pair of primary sloped surfaces in the thicknessdirection.

Preferably, the slit includes a pair of horizontal surfaces extending inthe primary scanning direction and perpendicular to the thicknessdirection, and each of the horizontal surfaces is located between one ofthe pair of primary sloped surfaces and one of the pair of additionalsloped surfaces.

In a preferred embodiment, the sensor IC includes a photodetectingsurface perpendicular to the thickness direction, and the pair ofhorizontal surfaces is oriented in a same direction as thephotodetecting surface.

In a preferred embodiment, the sensor IC includes a photodetectingsurface perpendicular to the thickness direction, and the pair ofhorizontal surfaces is configured to face the photodetecting surface.

In a preferred embodiment of the present invention, the housing includesa slit facing the sensor IC, and the support member includes aprojecting portion extending into the slit.

According to an embodiment of the first or second aspect of the presentinvention, preferably, the support member includes a cavity elongate inthe primary scanning direction, and the lens unit is fitted in thecavity.

According to an embodiment of the first or second aspect of the presentinvention, preferably, the support member includes a recessed portionformed so as to recede in the thickness direction orthogonal to both ofthe primary scanning direction and the secondary scanning direction, andthe lens unit is fitted in the recessed portion.

According to an embodiment of the first or second aspect of the presentinvention, more preferably, the image sensor module further includes asubstrate on which the sensor IC is mounted. The light source unitincludes: an LED module provided with at least one LED chip, at leastone lead on which the LED chip is mounted, and a resin package coveringa part of the lead and including an opening through which the LED chipis exposed; and a light guide elongate in the primary scanning directionas a whole and including an incidence surface facing the opening, areflection surface that reflects light from the incidence surface, andan output surface that outputs the light from the reflection surface ina form of a linear light beam elongate in the primary scanningdirection. The lead includes a terminal portion sticking out through theresin package in the thickness direction, extending from a positionretracted in the secondary scanning direction with respect to theopening.

Preferably, the substrate and at least a part of the light guide aredeviated from each other as viewed in the secondary scanning direction.

With the above arrangements, since the reflection surface is provided onthe light path extending from the objected to be read to the sensor IC,the light can be properly conducted along the desired path. Thus, it ispossible, for example, to align the optical axis of the lens unit alongthe secondary scanning direction. As a result, in the image sensormodule of the present invention, the length in the secondary scanningdirection can be increased, thereby increasing the total length of theoptical path, while the thickness of the module can be reduced. Inaddition, by fitting the plate-like support member in the housing, theoverall rigidity can be increased, while the thickness of the imagesensor module can be reduced.

According to a third aspect of the present invention, there is providedan image sensor module including: a light source unit that emits alinear light beam elongate in a primary scanning direction to an objectto be read; a light guide member including an entrance portion facingthe object, a primary reflection surface that reflects light from theentrance portion, and an output portion spaced from the entrance portionin a secondary scanning direction; a sensor IC that receives the lightfrom the object through the light guide member; and a housing that holdsthe light source unit and the light guide member. The entrance portionincludes an entrance lens surface, and the output portion includes anoutput lens surface.

Preferably, a substrate is provided for supporting the sensor IC andfixed to the light guide member.

Preferably, the light guide member includes an additional reflectionsurface spaced from the primary reflection surface in the secondaryscanning direction.

Other features and advantages of the present invention will become moreapparent through detailed description given hereunder with reference tothe accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing an image sensor module according to afirst embodiment of the present invention.

FIG. 2 is a plan view showing a housing employed in the image sensormodule shown in FIG. 1.

FIG. 3 is a cross-sectional view taken along a line III-III in FIG. 2.

FIG. 4 is a cross-sectional view taken along a line VI-VI in FIG. 2.

FIG. 5 is a front view showing an LED module of a light source unitemployed in the image sensor module shown in FIG. 1.

FIG. 6 is a side view of the LED module of the light source unitemployed in the image sensor module shown in FIG. 1.

FIG. 7 is a cross-sectional view of the light source unit taken along aline VII-VII in FIG. 5.

FIG. 8 is a cross-sectional view of the light source unit taken along aline VIII-VIII in FIG. 5.

FIG. 9 is an enlarged fragmentary front view showing the opening of theLED module shown in FIG. 5.

FIG. 10 is a fragmentary cross-sectional view taken along a line X-X inFIG. 9.

FIG. 11 is a perspective view showing a support member employed in theimage sensor module shown in FIG. 1.

FIG. 12 is a cross-sectional view showing an example of themanufacturing process of the support member shown in FIG. 11.

FIG. 13 is a cross-sectional view showing an image sensor moduleaccording to a second embodiment of the present invention.

FIG. 14 is a perspective view showing a support member employed in theimage sensor module shown in FIG. 13.

FIG. 15 is a cross-sectional view showing an example of themanufacturing process of the support member shown in FIG. 13.

FIG. 16 is a cross-sectional view showing an image sensor moduleaccording to a third embodiment of the present invention.

FIG. 17 is an enlarged cross-sectional view showing a support member anda lens unit shown in FIG. 16.

FIG. 18 is a plan view showing an image sensor module according to afourth embodiment of the present invention.

FIG. 19 is a cross-sectional view taken along a line XIX-XIX in FIG. 18.

FIG. 20 is an enlarged cross-sectional view showing a support member anda lens unit shown in FIG. 19.

FIG. 21 is a cross-sectional view showing a variation of the supportmember and a light shielding member shown in FIG. 20.

FIG. 22 is a cross-sectional view showing another variation of thesupport member and the light shielding member shown in FIG. 20.

FIG. 23 is a cross-sectional view showing an image sensor moduleaccording to a fifth embodiment of the present invention.

FIG. 24 is an enlarged cross-sectional view showing a support member anda lens unit shown in FIG. 23.

FIG. 25 is a cross-sectional view showing a variation of the supportmember shown in FIG. 24.

FIG. 26 is a cross-sectional view showing an image sensor moduleaccording to a sixth embodiment of the present invention.

FIG. 27 is a cross-sectional view showing an image sensor moduleaccording to a seventh embodiment of the present invention.

FIG. 28 is an enlarged cross-sectional view showing a support member andso forth shown in FIG. 27.

FIG. 29 is a cross-sectional view showing an image sensor moduleaccording to an eighth embodiment of the present invention.

FIG. 30 is an enlarged cross-sectional view showing a support member andso forth shown in FIG. 29.

FIG. 31 is a cross-sectional view showing an image sensor moduleaccording to a ninth embodiment of the present invention.

FIG. 32 is an enlarged cross-sectional view showing a light guide membershown in FIG. 31.

FIG. 33 is a cross-sectional view showing an image sensor moduleaccording to a tenth embodiment of the present invention.

FIG. 34 is an enlarged fragmentary cross-sectional view of the imagesensor module shown in FIG. 33.

FIG. 35 is an enlarged cross-sectional view showing a slit shown in FIG.34.

FIG. 36 is a fragmentary cross-sectional view showing an image sensormodule according to an eleventh embodiment of the present invention.

FIG. 37 is a cross-sectional view showing an image sensor moduleaccording to a twelfth embodiment of the present invention.

FIG. 38 is a cross-sectional view showing an example of a conventionalimage sensor module.

EMBODIMENTS TO CARRY OUT INVENTION

Preferred embodiments of the present invention will be described belowreferring to the drawings.

FIGS. 1, 3, and 4 illustrate an image sensor module according to a firstembodiment of the present invention. The image sensor module 101according to this embodiment includes a light source unit 200, a supportmember 300, a lens unit 400, a sensor IC 500, a substrate 600, a housing700, and a transmission plate 800. FIG. 2 is a plan view showing thehousing 700. FIGS. 3 and 4 are cross-sectional views of the image sensormodule 101, and the positions of the respective cutting lines areindicated in FIG. 2. The image sensor module 101 may be incorporated,for example, in a document scanner designed to optically read charactersand images printed on an object 890 to be read and generate electronicdata containing those characters and images.

The housing 700 defines the outer shape of the image sensor module 101,and encloses and supports the relevant components. The housing 700 has athickness direction z orthogonal to both of a primary scanning directionx and a secondary scanning direction y. The housing 700 has an elongateshape extending in the primary scanning direction x, and has a generallyrectangular cross-sectional shape taken in the secondary scanningdirection y and the thickness direction z. The housing 700 may be formedof, for example, a liquid crystal polymer resin.

As shown in FIGS. 2 to 4, the housing 700 includes a recessed portion710 and a recessed portion 720 formed so as to recede in directionsopposite to each other in the thickness direction 2. The recessedportion 710 and the recessed portion 720 have a rectangular shape whenviewed in the thickness direction z. The recessed portion 710 is openupward in the thickness direction z in FIG. 3, and the recessed portion720 is open downward in the thickness direction z in FIG. 3. The housing700 includes, inside the recessed portion 710, a light source chamber711 and a support region 712 in which the support member 300 is placed.The support region 712 includes support surfaces 713, 714 perpendicularto the thickness direction z and an elevated portion 715 protruding inthe thickness direction z. In addition, the support region 712 includesa groove 716 formed so as to penetrate in the thickness direction z, ata position overlapping the sensor IC 500 when viewed in the thicknessdirection z. The upper end of the groove 716 in the thickness directionz communicates with the recessed portion 710, and the lower endcommunicates with the recessed portion 720.

As shown in FIG. 3, the light source chamber 711 is located on the leftside in the recessed portion 710 as illustrated, and the support region712 is located on the right of the light source chamber 711 asillustrated. The elevated portion 715 is located on the left of thesupport surface 713 and the support surface 714 in FIG. 3. The supportsurface 713 is located on the left of the support surface 714 in FIG. 3.The support surface 714 is located at the right end portion of therecessed portion 710 in FIG. 3. The length of the support surface 714 inthe secondary scanning direction y is shorter than the length of thesupport surface 713 in the secondary scanning direction y. The groove716 is located between the support surface 713 and the support surface714 in the secondary scanning direction y.

The light source chamber 711 includes a terminal slot 717. As shown inFIGS. 2 and 4, the terminal slot 717 is located at an end portion of thehousing 700 in the primary scanning direction x. The terminal slot 717penetrates through the housing 700 in the thickness direction z, and hasa rectangular cross-section.

The substrate 600 is composed of an insulative material such as ceramicsor glass epoxy resin, and a non-illustrated wiring pattern formed on theinsulative material, and has an elongate rectangular shape extending inthe primary scanning direction x. The substrate 600 is accommodated inthe recessed portion 720 of the housing 700, and fixed to the housing700, for example via an adhesive. As shown in FIG. 3, the sensor IC 500is mounted on the substrate 600.

The transmission plate 800 is a plate-shaped member formed of atransparent material such as glass, and disposed so as to cover theupper face of the recessed portion 710 in the thickness direction z inFIG. 3.

The light source unit 200 serves to emit a linear light beam necessaryfor the image sensor module 101 to read images, and includes an LEDmodule 210, a light guide 280, and a reflector 285.

The LED module 210 is the device responsible for the light emittingfunction of the light source unit 200, and includes LED chips 221, 222,223, Zener diodes 224, 225, leads 241, 242, 243, 244, and a resinpackage 270 as shown in FIGS. 5 and 6.

The resin package 270 is formed of a white resin such as a liquidcrystal polymer resin or an epoxy resin, and covers a part of each ofthe leads 241, 242, 243, 244. The resin package 270 includes an opening271 and a plurality of positioning holes 272. The opening 271 is locatedclose to an end portion of the resin package 270 in the secondaryscanning direction y, and has a circular cross-section. The positioningholes 272 are located so as not to interfere with the leads 241, 242,243, 244, and penetrate through the resin package 270 in thisembodiment.

As shown in FIGS. 5 and 9, the lead 241 includes a mounting portion 251and a terminal portion 255. As a whole, the lead 241 includes anelongate portion extending in the secondary scanning direction y and aportion extending in the thickness direction 2. The mounting portion 251is located on the left side in the elongate portion extending in thesecondary scanning direction y in FIG. 5, and the LED chips 221, 222,223 and the Zener diode 224, 225 are mounted on the mounting portion251. In this embodiment, the mounting portion 251 of the lead 241 has anhourglass shape in which a portion thereof is smaller in the thicknessdirection z than the remaining portions. The mounting portion 251 isexposed in the opening 271 of the resin package 270. The terminalportion 255 projects downward in the thickness direction z from theresin package 270, and is connected to the substrate 600.

The lead 242 includes a wire bonding portion 252 and a terminal portion256. As a whole, the lead 242 includes an elongate portion extending inthe secondary scanning direction y and a portion extending in thethickness direction z. The wire bonding portion 252 is located close tothe left end of the elongate portion extending in the secondary scanningdirection y in FIG. 5. In this embodiment, the wire bonding portion 252projects downward in the thickness direction z toward the mountingportion 251 of the lead 241. The wire bonding portion 252 is exposed inthe opening 271 of the resin package 270. The terminal portion 256projects downward in the thickness direction z from the resin package270, and is connected to the substrate 600.

The lead 243 includes a wire bonding portion 253 and a terminal portion257. As a whole, the lead 243 includes a portion extending in thesecondary scanning direction y and a portion extending in the thicknessdirection z. The wire bonding portion 253 is located close to the leftend of the portion extending in the secondary scanning direction y inFIG. 5. In this embodiment, the wire bonding portion 253 projects upwardin the thickness direction z toward the mounting portion 251 of the lead241. The wire bonding portion 253 is exposed in the opening 271 of theresin package 270. The terminal portion 257 projects downward in thethickness direction z from the resin package 270, and is connected tothe substrate 600.

The lead 244 includes a wire bonding portion 254 and a terminal portion258. As a whole, the lead 244 includes a portion extending in thesecondary scanning direction y and a portion extending in the thicknessdirection z. The wire bonding portion 254 is located close to the leftend of the portion extending in the secondary scanning direction y inFIG. 5. In this embodiment, the wire bonding portion 254 is located inthe lower right region in the mounting portion 251 and on the right ofthe wire bonding portion 253, in FIG. 9. The wire bonding portion 254 isexposed in the opening 271 of the resin package 270. The terminalportion 258 projects downward in the thickness direction z from theresin package 270, and is connected to the substrate 600.

The LED chip 221 emits green light in this embodiment. As shown in FIGS.9 and 10, the LED chip 221 includes a submount substrate 221 a, asemiconductor layer 221 b, and a pair of surface substrates 231. Thesubmount substrate 221 a is, for example, formed of Si. Thesemiconductor layer 221 b is for example formed of a GaN-basedsemiconductor, and composed of an n-type semiconductor layer, a p-typesemiconductor layer, and an active layer (none illustrated) interleavedbetween the n-type semiconductor layer and the p-type semiconductorlayer. The pair of surface substrates 231 is formed on the submountsubstrate 221 a, and electrically connected to the n-type semiconductorlayer and the p-type semiconductor layer.

The LED chip 222 emits blue light in this embodiment. Here, referencenumerals of constituent of the LED chip 222 corresponding to therespective constituents of the LED chip 221 are indicated in parenthesesin FIG. 10, for clearer understanding. The LED chip 222 includes asubmount substrate 222 a, a semiconductor layer 222 b, and a pair ofsurface substrates 232. The submount substrate 222 a is for exampleformed of Si, and transparent. The semiconductor layer 222 b is forexample formed of a GaN-based semiconductor, and composed of an n-typesemiconductor layer, a p-type semiconductor layer, and an active layer(none illustrated) interleaved between the n-type semiconductor layerand the p-type semiconductor layer. The pair of surface substrates 232is formed on the submount substrate 222 a, and electrically connected tothe n-type semiconductor layer and the p-type semiconductor layer.

The LED chip 223 emits red light in this embodiment. As shown in FIGS. 9and 10, the LED chip 223 includes a semiconductor layer formed of forexample a GaAs-based semiconductor material, a surface substrate 233,and a back substrate 234. The semiconductor layer is composed of ann-type semiconductor layer, a p-type semiconductor layer, and an activelayer (none illustrated) interleaved between the n-type semiconductorlayer and the p-type semiconductor layer. The surface substrate 233 isprovided on the upper face of the LED chip 223 in the thicknessdirection z. The back substrate 234 is provided under the LED chip 223in the thickness direction z.

The Zener diode 224 serves to prevent the LED chip 221 from beingsubjected to an excessive voltage. The Zener diode 224 includes asurface substrate 235 and a back substrate 236. The Zener diode 225serves to prevent the LED chip 222 from being subjected to an excessivevoltage. The Zener diode 225 includes a surface substrate 237 and a backsubstrate 238.

The LED chips 221, 222 are aligned in the thickness direction z, andmounted on the mounting portion 251 of the lead 241 via a dielectriclayer 262. In this embodiment the dielectric layer 262 is transparent,and for example formed of a resin. The Zener diodes 224, 225 are alignedin the thickness direction z, and respectively located on the right ofthe LED chips 221, 222 in the secondary scanning direction y. The LEDchip 223 is located on the opposite side of the LED chips 221, 222 inthe secondary scanning direction y, across the Zener diodes 224, 225.The LED chip 223 and the Zener diodes 224, 225 are mounted on themounting portion 251 of the lead 241 via a conductive layer 261. To bemore detailed, the back substrate 234 of the LED chip 223 and the backsubstrates 236, 238 of the Zener diodes 224, 225 are electricallyconnected to the lead 241 via the conductive layer 261. The conductivelayer 261 is, for example, formed of Ag.

The LED chips 221, 222, 223 and the Zener diodes 224, 225 are mountedthrough the following process. First, a conductive paste to form theconductive layer 261 is applied to the mounting portion 251 of the lead241. Then the LED chip 223 and the Zener diodes 224, 225 are bonded tothe conductive paste. Upon solidifying the conductive paste, for exampleby sintering, the conductive layer 261 is obtained. Then a resin pasteto form the dielectric layer 262 is applied to the mounting portion 251,and the LED chips 221, 222 are bonded on the resin paste. Uponsolidifying the resin paste, the dielectric layer 262 is obtained.

Through the mentioned process, the dielectric layer 262 is formed afterthe conductive layer 261 is formed. Accordingly, in the case where theapplication region of the conductive paste and the application region ofthe resin paste overlap each other, the conductive layer 261 isinterposed between a part of the dielectric layer 262 and the mountingportion 251 of the lead 241. FIGS. 9 and 10 illustrate the conductivelayer 261 and the dielectric layer 262 formed under the mentionedcondition. The conductive layer 261 and the dielectric layer 262 may beformed so as not to overlap, depending on the application range of thepastes. However, the dielectric layer 262 is unable to be interposedbetween the conductive layer 261 and the mounting portion 251 of thelead 241, through the sequence of the mentioned process.

One of the pair of surface substrates 231 of the LED chip 221 isconnected to the mounting portion 251 of the lead 241 via a wire 265,and the other is connected to the wire bonding portion 252 of the lead242 via the wire 265. One of the pair of surface substrates 232 of theLED chip 222 is connected to the mounting portion 251 of the lead 241via the wire 265, and the other is connected to the wire bonding portion253 of the lead 243 via the wire 265.

The surface substrate 233 of the LED chip 223 is connected to the wirebonding portion 254 of the lead 244 via the wire 265. The surfacesubstrate 235 of the Zener diode 224 is connected to the wire bondingportion 252 of the lead 242 via the wire 265, and the surface substrate237 of the Zener diode 225 is connected to the wire bonding portion 253of the lead 243 via the wire 265.

The light guide 280 serves to convert the light from the LED module 210into a linear light beam extending in the primary scanning direction x,and for example formed of a transparent acrylic resin such as polymethylmethacrylate (PMMA). The light guide 280 has an elongate column shapeextending in the primary scanning direction x and includes, as shown inFIGS. 3 and 8, an incidence surface 281, a reflection surface 282, andan output surface 283.

The incidence surface 281 corresponds to an end face of the light guide280 in the primary scanning direction x, and disposed so as to close theopening 271 of the resin package 270 of the LED module 210 and to opposethe LED chips 221, 222, 223. The reflection surface 282 is an elongatesurface extending in the primary scanning direction x, and located alongthe lower left portion of the light guide 280 shown in FIG. 3. Thereflection surface 282 serves to reflect the light proceeding throughinside the light guide 280 after entering through the incidence surface281. The reflection surface 282 may be a surface on which minute bumpsand dips are formed, and a surface on which a white paint is applied.The output surface 283 is an elongate surface extending in the primaryscanning direction x, and formed in a shape having an arcuatecross-section in this embodiment. The light reflected by the reflectionsurface 282 is outputted through the output surface 283 in a form of alinear light beam extending in the primary scanning direction x.

The reflector 285 serves to place the light guide 280 in position in theLED module 210 and to prevent accidental leakage of the light from thelight guide 280, and is formed of a white resin, for example. Thereflector 285 includes a base portion 286 and a semicylindrical portion287. The base portion 286 has a rectangular shape similar in shape andsize to the resin package 270 of the LED module 210, when viewed in theprimary scanning direction x. The base portion 286 includes a pluralityof projections 288. As shown in FIG. 7, the projections 288 are eachfitted in the corresponding positioning hole 272 of the resin package270 of the LED module 210. Accordingly, the reflector 285 is properlypositioned with respect to the LED module 210.

The semicylindrical portion 287 is an elongate portion extending in theprimary scanning direction x and, as shown in FIG. 3, supports the lightguide 280. A portion of the reflector 285 facing the reflection surface282 of the light guide 280 serves to return the light outputted from thereflection surface 282 to the light guide 280. By supporting the lightguide 280 with the semicylindrical portion 287, the light guide 280 isfixed to the reflector 285. Therefore, the light guide 280 is properlypositioned with respect to the LED module 210, together with thereflector 285.

The LED chips 221, 222, 223 and the light guide 280 are retracted to theleft in the secondary scanning direction y, with respect to the terminalportions 255, 256, 257, 258. The substrate 600 has a size in thesecondary scanning direction y just enough for connection with theterminal portions 255, 256, 257, 258, and an abundant vacant space isunavailable. Therefore, the LED chip 221, 222, 223 and the light guide280 are retracted to the left from the substrate 600 in the secondaryscanning direction y. In this embodiment, the light guide 280 and thesubstrate 600 are located so as not to overlap at all in the secondaryscanning direction y. However, in the present invention, the light guide280 and the substrate 600 may partially overlap in the secondaryscanning direction y.

The support member 300 includes, as shown in FIG. 11, an elongatebar-shaped transmissive portion 310 extending in the primary scanningdirection x, and non-transmissive layers 320, 330 located on therespective side faces of the transmissive portion 310 in the secondaryscanning direction y. The transmissive portion 310 is formed of atransparent acrylic resin, and includes a bottom face 311 perpendicularto the thickness direction z, a sloped surface 312 connected to the leftedge of the bottom face 311 in the secondary scanning direction y inFIG. 11, and another sloped surface 313 connected to the right edge ofthe bottom face 311 in the secondary scanning direction y in FIG. 11.The sloped surface 312 is inclined, as shown in FIG. 3, so as to becloser to the light guide 280 of the light source unit 200 in thesecondary scanning direction y, as proceeding away from the bottom face311 in the thickness direction z. The angle between the sloped surface312 and the bottom face 311 is, for example, 45 degrees. The slopedsurface 313 is inclined, as shown in FIG. 3, so as to be closer to thelight guide 280 of the light source unit 200 in the secondary scanningdirection y, as proceeding away from the bottom face 311 in thethickness direction z. The angle between the sloped surface 313 and thebottom face 311 is, for example, 45 degrees. Further, the transmissiveportion 310 includes a cavity 314 of an elongate shape extending in theprimary scanning direction x. The cavity 314 has a rectangular shapewhen viewed in the direction x. In this embodiment, the cavity 314penetrates through the transmissive portion 310 in the primary scanningdirection x. Here, the cavity 314 may be formed with an opening only oneither side in the primary scanning direction x. The lens unit 400 isaccommodated in the cavity 314. In addition, the transmissive portion310 includes a plurality of holes 315 extending in the thicknessdirection z so as to reach the cavity 314.

The non-transmissive layer 320 is formed of aluminum for example, so asto cover the sloped surface 312. The non-transmissive layer 330 is alsoformed of aluminum, so as to cover the sloped surface 313.

The support member 300 includes a reflection surface 321 provided alongthe interface between the sloped surface 312 and the non-transmissivelayer 320, and a reflection surface 331 provided along the interfacebetween the sloped surface 313 and the non-transmissive layer 330. Morespecifically, the reflection surface 321 is the surface of thenon-transmissive layer 320 disposed in contact with the sloped surface312, and the reflection surface 331 is the surface of thenon-transmissive layer 330 disposed in contact with the sloped surface313. The surface of the non-transmissive layer 320 opposite to thereflection surface 321 abuts against the upper end portion of theelevated portion 715 in the thickness direction z in FIG. 3. The lowerend portion of the surface of the non-transmissive layer 330 in thethickness direction 2 opposite to the reflection surface 331 abutsagainst the right sidewall of the recessed portion 710 in FIG. 3. Withsuch a configuration, the position of the support member 300 in thesecondary scanning direction y is fixed.

FIG. 12 illustrates an example of the manufacturing process of thesupport member 300. To manufacture the transmissive portion 310 thatserves as the base for the support member 300, a pair of molds 340, 350facing each other is employed, as shown in FIG. 12. The mold 340includes a cavity 341, and the mold 350 includes a cavity 351. Thesidewalls of the cavity 341 and cavity 351 are each inclined by 45degrees with respect to the bottom face, such that upon combining thecavity 341 and the cavity 351, the outer shape of the transmissiveportion 310 is defined. The transmissive portion 310 can be formed uponintroducing an acrylic resin of a liquid phase in the cavity 341 and thecavity 351 with the lens unit 400 fixed therebetween, and solidifyingthe acrylic resin. To support the lens unit 400, a support pin 342 isprovided in the cavity 341, and a support pin 352 is provided in thecavity 351. At the positions corresponding to the support pins 342, 352,the holes 315 are formed.

The cavity 314 is formed because the lens unit 400 is held between themold 340 and the mold 350. Such a manufacturing process is feasiblebecause the lens unit 400 and the transmissive portion 310 are bothformed of a resin and hence barely different in thermal expansioncoefficient. The support member 300 accommodating therein the lens unit400 can be efficiently manufactured through the mentioned manufacturingprocess. In addition, the mentioned manufacturing process allows thecavity 314 to be formed with an opening on neither of the end portionsin the primary scanning direction x.

The non-transmissive layers 320, 330 can be formed by depositingaluminum, for example through a sputtering process, on the slopedsurface 312 and the sloped surface 313 of the transmissive portion 310,respectively.

The lens unit 400 is formed in an elongate shape extending in theprimary scanning direction x, and includes an incidence surface 401 andan output surface 402 oriented in opposite directions in the secondaryscanning direction y. As shown in FIG. 3, the incidence surface 401 islocated at a position more distant from the sensor IC 500 than theoutput surface 402, in the secondary scanning direction y. The lens unit400 includes a plurality of rod lenses and a housing, for example formedof a resin, enclosing the rod lenses. The rod lenses are configured toform an upright image of the content of the object to be read 890 inequal magnification in the sensor IC 500, and has an optical axisaligned with the secondary scanning direction y and perpendicular to theprimary scanning direction x.

As shown in FIG. 3, the lens unit 400 is fitted in the cavity 314 of thesupport member 300 such that the optical axis is aligned with thesecondary scanning direction y. The incidence surface 401 and the outputsurface 402 are located so as to overlap the reflection surfaces 321,331, respectively, when viewed in the secondary scanning direction y.Light incident on the reflection surface 321 along the thicknessdirection 2 is reflected by the reflection surface 321 and proceedstoward the incidence surface 401 in the secondary scanning direction y.The light introduced through the incidence surface 401 passes throughthe rod lenses in the lens unit 400 and is outputted through the outputsurface 402 in the secondary scanning direction y. The light outputtedthrough the output surface 402 is reflected by the reflection surface331 so as to proceed in the thickness direction z, and then reaches thesensor IC 500 through the groove 716.

The sensor IC 500 has a photoelectric conversion function to convertreceived light into an electrical signal, and is mounted on thesubstrate 600. The sensor IC 500 includes a plurality of photodetectingsurfaces (not shown) aligned in the primary scanning direction x. Thelens unit 400 forms an image on the photodetecting surface based on thelight reflected by the object to be read 890.

The transmission plate 800 includes a light shielding layer 810. Thelight shielding layer 810 may be formed by applying a black paint to apart of the lower face of the transmission plate 800, or adheringthereto a black resin tape. The light shielding layer 810 has anelongate shape extending in the primary scanning direction x, andoverlaps a portion of the lens unit 400 in the vicinity of the right endportion thereof, in the secondary scanning direction y.

Advantageous effects of the image sensor module 101 will now bedescribed hereunder.

In this embodiment, as shown in FIG. 3, the optical path arranged fromthe object to be read 890 to the sensor IC 500 is bent, and the sectionpassing through the lens unit 400 is parallel to the secondary scanningdirection y. Accordingly, prolonging the optical path does not incur anincrease in size of the image sensor module 101 in the thicknessdirection z. The reflection surfaces 321, 331 that serve to bend theoptical path are provided in the support member 300. The support member300 is supported by the transmissive portion 310 formed of an acrylicresin, and hence can participate in securing a part of the rigidity ofthe housing 700. In this embodiment, the support member 300 abutsagainst the right sidewall of the recessed portion 710 in FIG. 3 and theelevated portion 715, and thus prevents the housing 700 from beingdistorted. Therefore, the image sensor module 101 can be made thinner inthe thickness direction z, without compromising the rigidity of thehousing 700.

In this embodiment, the sloped surfaces 312, 313 of the transmissiveportion 310 are formed by the shape of the molds 340, 350. Such amanufacturing process suppresses fluctuation of the shape of the slopedsurfaces 312, 313, compared with the case of, for example, cutting anacrylic plate having an elongate rectangular cross section to form thesloped surfaces 312, 313.

Forming the substrate 600 in a width that keeps the substrate 600 fromoverlapping the light guide 280 and the LED chips 221, 222, 223 in thesecondary scanning direction y contributes to minimizing unnecessaryspace on the substrate 600, which leads to reduction in manufacturingcost.

FIGS. 13 through 37 illustrate other embodiments of the presentinvention. In these drawings, constituents that are the same as orsimilar to those cited in the embodiment are given the same numeral asabove.

FIGS. 13 and 14 illustrate an image sensor module according to a secondembodiment of the present invention. The image sensor module 102according to this embodiment is different from the image sensor module101 in the shape of the support member 300, and the remaining portionsare configured in the same way as the image sensor module 101.

As shown in FIGS. 13 and 14, the transmissive portion 310 of the supportmember 300 in this embodiment includes a recessed portion 316, in placeof the cavity 314. The recessed portion 316 is formed so as to recedetoward the bottom face 311 in the thickness direction z, from thesurface of the transmissive portion 310 opposite to the bottom face 311.The recessed portion 316 thus configured can be formed, as shown in FIG.15, for example by placing the lens unit 400 on the bottom face of thecavity 341 of the mold 340. Such a manufacturing method eliminates theneed to use the support pins 342, 352.

FIGS. 16 and 17 illustrate an image sensor module according to a thirdembodiment of the present invention. The image sensor module 103 shownin FIGS. 16 and 17 is different from the image sensor module 102 in theconfiguration of the support member 300, and further includes a lightshielding member 360. The remaining portions of the image sensor module103 are configured in the same way as those of the image sensor module102. FIG. 17 is an enlarged cross-sectional view of the support member300, the lens unit 400, and the light shielding member 360 extractedfrom FIG. 16.

The support member 300 according to this embodiment is formed of atransparent acrylic resin, in generally the same shape as thetransmissive portion 310 shown in FIG. 14. The support member 300according to this embodiment includes a bottom face 301 supported by thehousing 700, a sloped surface 302 and a sloped surface 303 inclined withrespect to the bottom face 301, and a top face 304 located opposite tothe bottom face 301 in the thickness direction z. In addition, thesupport member 300 includes a recessed portion 305 formed so as torecede in the thickness direction z. The recessed portion 305 is formedso as to recede from the top face 304 toward the bottom face 301. Thelens unit 400 is fitted in the recessed portion 305.

As shown in FIGS. 16 and 17, the sloped surface 302 is located at theleft end of the support member 300 and the sloped surface 303 is locatedat the right end of the support member 300, as illustrated. The slopedsurface 302 and the sloped surface 303 are inclined so as to be closerto the light guide 280 of the light source unit 200 in the secondaryscanning direction y, as proceeding away from the bottom face 301 in thethickness direction 2. The angle defined between the sloped surface 302and the bottom face 301, and the angle defined between the slopedsurface 303 and the bottom face 301 are, for example, 45 degrees. Thesloped surface 302 and the sloped surface 303 are mirror-finished, andtotally reflect the light proceeding through inside the support member300 at the interface with air, to the inside of the support member 300.In this embodiment, a part of the sloped surface 302 constitutes areflection surface 302 a, and a part of the sloped surface 303constitutes a reflection surface 303 a. The reflection surface 302 areflects the light from the object to be read 890 toward the incidencesurface 401. The reflection surface 303 a reflects the light from theoutput surface 402 toward the sensor IC 500.

Here, the sloped surface 302 and the sloped surface 303 of the supportmember 300 formed of an acrylic resin possess a certain level ofreflectance even without the mirror finish. Accordingly, it is notmandatory to apply the mirror finish to the sloped surface 302 and thesloped surface 303.

In this embodiment also, the optical path arranged from the object to beread 890 to the sensor IC 500 is bent, and the section passing throughthe lens unit 400 is parallel to the secondary scanning direction y.Accordingly, prolonging the optical path does not incur an increase insize of the image sensor module 103 in the thickness direction z.Further, the support member 300 is formed of an acrylic resin and hencecan participate in securing a part of the rigidity of the housing 700.In this embodiment also, the support member 300 abuts against the rightsidewall of the recessed portion 710 in FIG. 16 and the elevated portion715, and thus prevents the housing 700 from being distorted. Therefore,the image sensor module 103 can be made thinner in the thicknessdirection z, without compromising the rigidity of the housing 700.

The light shielding member 360 covers the support member 300 so as toexpose at least the reflection surface 302 a and the reflection surface303 a. The light shielding member 360 may be an adhesive tape made of ablack resin and adhered to the support member 300. As shown in FIG. 17,the light shielding member 360 includes a sloped surface anti-reflectionportion 361, a bottom face anti-reflection portion 362, a bottom facecover portion 363, a top face cover portion 364, and a sloped surfaceanti-reflection portion 365. Here, the light shielding member 360 thatprovides the same effect can also be obtained by printing a black resinon the surface of the support member 300.

Further, the light shielding member 360 may be formed by spraying apaint or through a sputtering process.

As shown in FIG. 17, the sloped surface anti-reflection portion 361 isin close contact with a portion of the sloped surface 302. The portionof the sloped surface 302 in close contact with the sloped surfaceanti-reflection portion 361 is unable to serve as a reflection surface.On the contrary, the portion of the sloped surface 302 uncovered withthe sloped surface anti-reflection portion 361 constitutes an interfacewith air, and hence constitutes the reflection surface 302 a.

The bottom face anti-reflection portion 362 and the bottom face coverportion 363 cover the bottom face 301 so as to expose a portion thereof.The portion of the bottom face 301 uncovered with the bottom faceanti-reflection portion 362 and the bottom face cover portion 363constitutes an output portion 301 a through which the light from thereflection surface 303 a is outputted toward the sensor IC 500. As shownin FIG. 16, the output portion 301 a is disposed so as to oppose thegroove 716.

The bottom face anti-reflection portion 362 is in close contact with aportion of the bottom face 301 from the left end in FIG. 17 to the leftedge of the output portion 301 a. In this embodiment, the bottom faceanti-reflection portion 362 is formed integrally with the sloped surfaceanti-reflection portion 361.

The bottom face cover portion 363 covers a portion of the bottom face301 from the right end in FIG. 17 to the right edge of the outputportion 301 a.

Here, the bottom face anti-reflection portion 362 may be formed, forexample, by employing a black adhesive when the support member 300 isplaced on the support surface 713, instead of adhering a black tape orprinting a black resin. The black adhesive can be obtained, for example,by adding a dye to an adhesive composed of an epoxy resin. Likewise, thebottom face cover portion 363 may also be formed by bonding the supportmember 300 and the support surface 714 together with a black adhesive.

The top face cover portion 364 covers the majority of the top face 304.A portion of the top face 304 uncovered with the top face cover portion364 constitutes an entrance portion 304 a through which the light fromthe object to be read 890 is introduced. The entrance portion 304 a islocated at the left end of the support member 300 in FIG. 17, andoverlaps the reflection surface 302 a when viewed in the thicknessdirection z.

In the example shown in FIG. 17, the top face cover portion 364 alsocovers the lens unit 400. Such a configuration is obtained by formingthe light shielding member 360 after the lens unit 400 is placed in thesupport member 300. However, the light shielding member 360 may beformed before placing the lens unit 400 in the support member 300. Inthis case, the lens unit 400 is exposed through the light shieldingmember 360.

The sloped surface anti-reflection portion 365 is in close contact witha portion of the sloped surface 303. The portion of the sloped surface303 in close contact with the sloped surface anti-reflection portion 365is unable to serve as a reflection surface. On the contrary, the portionof the sloped surface 303 uncovered with the sloped surfaceanti-reflection portion 365 constitutes an interface with air, and henceconstitutes the reflection surface 303 a. The sloped surfaceanti-reflection portion 365 corresponds to the additional sloped surfaceanti-reflection portion in the present invention.

In the case where the light shielding member 360 is not provided, thelight that has entered through the top face 304 may be reflected by thebottom face 301, the sloped surface 302, and the sloped surface 303 soas to reach the sensor IC 500 as stray light without passing through thelens unit 400, for example as indicated by dash-dot-dot lines in FIG.17. In the case where the object to be read 890 contains for example ablack pattern, such stray light may disable the image sensor module fromrecognizing the black pattern. The light shielding member 360 serves toprevent such a malfunction.

The sloped surface anti-reflection portion 361, the bottom faceanti-reflection portion 362, and the sloped surface anti-reflectionportion 365 serve to suppress reflection to inside of the support member300, thereby preventing the stray light from proceeding inside thesupport member 300. The bottom face cover portion 363 prevents the straylight from being outputted from the support member 300. The top facecover portion 364 prevents intrusion of unnecessary light into thesupport member 300.

The function of the bottom face cover portion 363 may instead berealized by adjusting the shape of a portion of the housing 700 in thevicinity of the groove 716. For example, the groove 716 may be madenarrower, so that the region to be covered with the bottom face coverportion 363 is covered with the support surface 714.

Further, the top face cover portion 364 may be substituted with thelight shielding layer 810. Alternatively, an eave member may be providedon the housing 700 so as to block the light from an upper position inFIG. 16.

To prevent intrusion of unnecessary light into the support member 300,cover layers that respectively cover the sloped surface 302 and thesloped surface 303 may be provided. Such cover layers may be formed of ablack resin like the light shielding member 360. Here, it is preferablethat the cover portions are slightly spaced from the sloped surface 302and the sloped surface 303, so as not to affect the performance of thereflection surface 302 a and the reflection surface 303 a.

The provision of the light shielding member 360 on thelight-transmissive support member 300 may be applied to similar fields,without limitation to the image sensor module. In an LED printing headfor example, normal printing performance is disturbed when stray lightemerges in a light guide that guides the light from the LED. Adhering ablack adhesive tape or printing a black resin on the light guide isuseful for preventing such a situation.

FIGS. 18 and 19 illustrate an image sensor module according to a fourthembodiment of the present invention. The image sensor module 104 shownin FIGS. 18 and 19 may be incorporated, for example, in a documentscanner designed to optically read characters and images printed on theobject to be read 890 to thereby generate electronic data containingthose characters and images, as is the image sensor module 101. Althoughthe transmission plate 800 is fixed to the housing 700 in the imagesensor module 101 shown in FIG. 1, in the image sensor module 104according to this embodiment the housing 700 and the transmission plate800 are separated from each other. The transmission plate 800 accordingto this embodiment is fixed, for example, to the casing of a documentscanner in which the image sensor module 104 is incorporated. Except forsuch a difference in configuration, the basic structure of the imagesensor module 104 is similar to that of the image sensor module 101.FIG. 20 is an enlarged cross-sectional view of the support member 300and the lens unit 400 shown in FIG. 19. Referring to FIGS. 18 to 20, thedifference between the image sensor module 104 and the image sensormodule 101 will be described hereunder.

The support member 300 according to this embodiment is formed of atransparent acrylic resin, in a shape similar to the transmissiveportion 310 shown in FIG. 14. The support member 300 according to thisembodiment includes a bottom face 301 disposed in contact with thehousing 700, the sloped surface 302, the sloped surface 303, the topface 304 opposite to the bottom face 301 in the thickness direction z,and an upright surface 306 erected with respect to the bottom face 301and extending in the primary scanning direction x. In addition, thesupport member 300 includes the recessed portion 305 formed so as torecede in the thickness direction z. The recessed portion 305 is formedso as to recede from the top face 304 toward the bottom face 301. Thelens unit 400 is fitted in the recessed portion 305.

As shown in FIG. 20, the image sensor module 104 according to thisembodiment includes the light shielding member 360 that covers a part ofthe support member 300. The light shielding member 360 according to thisembodiment includes the top face cover portion 364 and the slopedsurface anti-reflection portion 365. Here, the top face cover portion364 and the sloped surface anti-reflection portion 365 according to thisembodiment are the same as the top face cover portion 364 and the slopedsurface anti-reflection portion 365 in the image sensor module 103. Theportion of the top face 304 uncovered with the top face cover portion364 constitutes the entrance portion 304 a through which the light fromthe object to be read 890 is introduced.

The sloped surface 302 according to this embodiment is shorter than thesloped surface of, for example, the support member 300 in the imagesensor module 103, because the upright surface 306 is provided.Therefore, unlike in the image sensor module 103, the sloped surfaceanti-reflection portion 361 is less important. However, in the casewhere the lens unit 400 is smaller and hence the sloped surface 302 hasto be made narrower, it is advantageous to provide the sloped surfaceanti-reflection portion 361.

As shown in FIG. 20, the bottom face 301 according to this embodimentincludes a pair of grooves 301 b recessed upward in the thicknessdirection z as illustrated. The grooves 301 b both extend in the primaryscanning direction x, and are spaced from each other in the scanningdirection y. The grooves 301 b each include a groove upright surface 301b 1 perpendicularly erected with respect to the bottom face 301, and agroove sloped surface 301 b 2 inclined with respect to the grooveupright surface 301 b 1 and the bottom face 301. In each of the grooves301 b, the groove upright surface 301 b 1 is located on the left of thegroove sloped surface 301 b 2 in the secondary scanning direction y inFIG. 20.

Further, the bottom face 301 includes a belt-like region 301 c locatedbetween the pair of grooves 301 b in the secondary scanning direction y.In this embodiment, the belt-like region 301 c is slightly recessedupward with respect to the remaining region of the bottom face 301, inthe thickness direction 2 in FIG. 20. Accordingly, a gap is definedbetween the support surface 713 and the belt-like region 301 c. Anon-illustrated adhesive for bonding the bottom face 301 and the supportsurface 713 is to be introduced in the gap. The adhesive introduced inthe gap further intrudes in the pair of grooves 301 b.

As shown in FIG. 19, the sloped surface 302 is located at the left endof the support member 300, and the sloped surface 303 is located at theright end of the support member 300, as illustrated. The sloped surface302 and the sloped surface 303 are inclined so as to be closer to thelight guide 280 of the light source unit 200 in the secondary scanningdirection y, as proceeding away from the bottom face 301 in thethickness direction z. The angle defined between the sloped surface 302and the bottom face 301, and the angle defined between the slopedsurface 303 and the bottom face 301 are, for example, 45 degrees. Thesloped surface 302 and the sloped surface 303 are mirror-finished, andtotally reflect the light proceeding through inside the support member300 at the interface with air, to the inside of the support member 300.The sloped surface 302 according to this embodiment corresponds to thereflection surface in the present invention, and reflects the light fromthe object to be read 890 toward the incidence surface 401. The portionof the sloped surface 303 according to this embodiment uncovered withthe sloped surface anti-reflection portion 365 constitutes thereflection surface 303 a that reflects the light from the output surface402 toward the sensor IC 500. The reflection surface 303 a correspondingto the additional reflection surface in the present invention.

As shown in FIG. 20, the recessed portion 305 according to thisembodiment includes a bottom groove 305 a, and bottom elevated portions305 b protruding upward with respect to the bottom groove 305 a in thethickness direction z as illustrated. The respective top faces of thebottom elevated portions 305 b serve to support the lens unit 400.

As shown in FIG. 20, the upright surface 306 is located at the left endof the support member 300 as illustrated, and perpendicularly erectedwith respect to the bottom face 301. The sloped surface 302 and thesloped surface 303 are inclined by 45 degrees with respect to theupright surface 306. In this embodiment, the upright surface 306 isformed so as to connect between the lower edge of the sloped surface 302in FIG. 20 and the left edge of the bottom face 301 in FIG. 20. Theupright surface 306 is located at a lower position from the lens unit400 in the thickness direction z in FIG. 20.

As shown in FIG. 19, the upright surface 306 is in contact with theelevated portion 715 of the housing 700. To be more detailed, theelevated portion 715 has a side face 715 a erected with respect to thesupport surface 713, and the upright surface 306 abuts against such sideface 715 a.

The transmission plate 800 according to this embodiment also includesthe light shielding layer 810. The light shielding layer 810 may beformed by applying a black paint to a part of the lower face of thetransmission plate 800, or adhering thereto a black resin tape. Thelight shielding layer 810 has an elongate shape extending in the primaryscanning direction x, and overlaps a portion of the lens unit 400 in thevicinity of the right end portion thereof, in the secondary scanningdirection y. The light shielding layer 810 serves to prevent intrusionof unnecessary light into the support member 300 from the sloped surface303.

In this embodiment also, the optical path arranged from the object to beread 890 to the sensor IC 500 is bent, and the section passing throughthe lens unit 400 is parallel to the secondary scanning direction y.Accordingly, prolonging the optical path does not incur an increase insize of the image sensor module 104 in the thickness direction z.Further, the support member 300 is formed of an acrylic resin and hencecan participate in securing a part of the rigidity of the housing 700.In this embodiment also, the support member 300 abuts against the rightsidewall of the recessed portion 710 in FIG. 16 and the elevated portion715, and thus prevents the housing 700 from being distorted. Therefore,the image sensor module 104 can be made thinner in the thicknessdirection 2, without compromising the rigidity of the housing 700.

Placing the support member 300 according to this embodiment in thehousing 700 such that the upright surface 306 abuts against the sideface 715 a facilitates the positioning of the support member 300 in thehousing 700. In the case of the support member 300 for example shown inFIG. 3, the support member 300 is only in contact with a corner of theelevated portion 715, and hence prone to step over the elevated portion715 when an excessive force is applied to the support member 300 whilesetting the support member 300. In contrast, in the case where thesupport member 300 has the upright surface 306, a surface-to-surfacecontact is realized and therefore the support member 300 can be moreaccurately and stably positioned. Such a configuration reduces defectsarising from the improper positioning of the support member 300 in thehousing 700, thereby improving the production yield and reducing themanufacturing cost.

The support member 300 according to this embodiment includes the pair ofgrooves 301 b, and the adhesive for bonding the bottom face 301 and thesupport surface 713 together is introduced in the pair of grooves 301 b.Because of the pair of grooves 301 b, the support member 300 is incontact with the adhesive via a larger area compared with the case wherethe adhesive is applied to a flat bottom face 301 such as the one shownin FIG. 17. Therefore, in the image sensor module 104 according to thisembodiment, the support member 300 can be more firmly fixed to thehousing 700.

Further, the upright surface 306 is perpendicular to the top face 304 onwhich the light from the object to be read 890 is incident. As indicatedby dash-dot-dot lines in FIG. 20, the light incident on the top face 304and deviated from the sloped surface 302 tends to proceed in thethickness direction z, and the upright surface 306 is parallel to thecourse of such light. Accordingly, the light introduced through the topface 304 is barely reflected by the upright surface 306, and henceemergence of stray light is suppressed in the support member 300. Asstated with reference to the image sensor module 103, the emergence ofstray light that does not pass through the lens unit 400 in the supportmember 300 leads to degradation in reading accuracy. Therefore, it ispreferable to form the upright surface 306 to suppress the emergence ofstray light, from the viewpoint of improving the reading accuracy.

Still further, in this embodiment the support member 300 includes thepair of grooves 301 b, and the grooves 301 b each include the grooveupright surface 301 b 1. Even though the light should proceed toward thesensor IC 500 in the secondary scanning direction y along the lower faceof the lens unit 400 in the support member 300, such light is reflectedby the groove upright surface 301 b and thus restricted from reachingthe right end of the support member 300 in FIG. 20.

FIGS. 21 and 22 illustrate a variation of the support member 300 and thelight shielding member 360 shown in FIG. 20. In the example shown inFIGS. 21 and 22, the light shielding member 360 includes the bottom faceanti-reflection portion 362 and the bottom face cover portion 363 thatcover the bottom face 301. In the example shown in FIG. 21, the bottomface anti-reflection portion 362 is split into three belt-like regionsso as to expose the pair of grooves 301 b. In contrast, in the exampleshown in FIG. 22, the bottom face anti-reflection portion 362 is formedas a single strip so as to cover the grooves 301 b. In these examples,the bottom face anti-reflection portion 362 serves to suppressreflection at the bottom face 301 as does the bottom faceanti-reflection portion 362 in the image sensor module 103. Here, in theexample shown in FIG. 22 the configuration of the bottom faceanti-reflection portion 362 is simplified and hence the formationprocess of the bottom face anti-reflection portion 362 on the bottomface 301 can be simplified, however, on the other hand, the adhesive(not shown) is not introduced in the grooves 301 b. In this case also,the pair of grooves 301 b can prevent unnecessary light from approachingthe sensor IC 500.

FIGS. 23 and 24 illustrate an image sensor module according to a fifthembodiment of the present invention. The image sensor module 105 shownin FIGS. 23 and 24 is different from the image sensor module 104 in theconfiguration of a part of the support member 300. The remainingportions of the image sensor module 105 are configured in the same wayas those of the image sensor module 104.

The support member 300 according to this embodiment includes an uprightsurface 307 erected with respect to the bottom face 301 and extending inthe primary scanning direction x. The upright surface 307 is locatedopposite to the upright surface 306 in the secondary scanning directiony across the lens unit 400. As shown in FIG. 23, the upright surface 307is located at the right end of the support member 300 as illustrated. Inthis embodiment, the upper end of the upright surface 307 is at the sameposition as the right end of the sloped surface 303 in the thicknessdirection z in FIG. 23. The sloped surface 303 according to thisembodiment is located so as to overlap the sloped surface 302 and theupright surface 307 is located so as to overlap the upright surface 306,when viewed in the secondary scanning direction y. The support member300 also includes a junction surface 308 parallel to the bottom face 301and connecting between the upper end of the upright surface 307 and theright end of the sloped surface 303 in FIG. 24.

The upright surface 307 is in contact with the housing 700. To be moredetailed, the housing 700 includes a sidewall 710 a oriented to therecessed portion 710 and erected from the right end of the supportsurface 714 in FIG. 23, and the upright surface 307 abuts against suchsidewall 710 a.

In this embodiment, the sloped surface 303 is shorter than that of theimage sensor module 104, and instead the junction surface 308 parallelto the bottom face 301 is provided. Accordingly, the light shieldingmember 360 according to this embodiment includes a junction surfacecover portion 366 that covers the junction surface 308, in place of thesloped surface anti-reflection portion 365. The junction surface coverportion 366 serves to shield the light proceeding from above in thethickness direction z in FIG. 23, as does the top face cover portion364.

With the mentioned configuration, the support member 300 can be set atthe intended position by squeezing the support member 300 into thehousing 700 with the upright surface 307 being made to abut the sidewall710 a.

In this embodiment, further, even though stray light should proceed inthe secondary scanning direction y along the lower face of the lens unit400 (dash-dot-dot lines in FIG. 24), such stray light is incident on theupright surface 307 instead of being reflected by the sloped surface303. Therefore, the stray light is less likely to be reflected towardthe sensor IC 500, compared with the case where the stray light isincident on the sloped surface 303.

Although the upright surface 306 is in contact with the side face 715 aof the elevated portion 715 in the example shown in FIG. 23, the uprightsurface 306 and the side face 715 d may be spaced from each other in thesecondary scanning direction y. Conversely, the upright surface 306 andthe side face 715 a may be in contact with each other and the uprightsurface 307 and the sidewall 710 a may be spaced from each other. Makingeither of the upright surface 306 and the upright surface 307 abutagainst the housing 700 facilitates the positioning of the supportmember 300 in the housing 700. However, from the viewpoint ofsuppressing distortion of the housing 700, it is preferable that atleast a part of the upright surface 306 or the sloped surface 302 is incontact with the housing 700 and at least a part of the upright surface307 or the sloped surface 303 is in contact with the housing 700.

FIG. 25 illustrates a variation of the support member 300 shown in FIG.24. The bottom elevated portion 305 b of the support member 300 shown inFIG. 25 includes a pair of elevated portion upright surface 305 b 1erected with respect to the bottom face 301. The lower end of theelevated portion upright surface 305 b 1 in the thickness direction z inFIG. 25 is, for example, generally at the same position as the upper endof the groove 301 b in the thickness direction z in FIG. 25. Such aconfiguration further restricts stray light from passing through theregion under the lens unit 400 in the support member 300 in FIG. 25.

FIG. 26 illustrates an image sensor module according to a sixthembodiment of the present invention. The image sensor module 106 shownin FIG. 26 is different from the image sensor module 104 in theconfiguration of a part of the support member 300 and the lightshielding member 360. The remaining portions of the image sensor module106 are configured in the same way as those of the image sensor module104.

The support member 300 according to this embodiment includes the uprightsurface 307 erected with respect to the bottom face 301 and extending inthe primary scanning direction x. The upright surface 307 is locatedopposite to the upright surface 306 in the secondary scanning directiony across the lens unit 400. As shown in FIG. 26, the upright surface 307is located at the right end of the support member 300 as illustrated. Inthis embodiment, the sloped surface 303 is located so as to overlap thesloped surface 302 and the upright surface 307 is located so as tooverlap the upright surface 306, when viewed in the secondary scanningdirection y. The support member 300 also includes a junction surface 308parallel to the upright surface 307 is formed so as to extend in thethickness direction z from the right end of the sloped surface 303 inFIG. 26.

Further, the support member 300 according to this embodiment includes aprojecting portion 309 fitted in the groove 716 of the housing 700. Theprojecting portion 309 sticks out from the right end portion of thebottom face 301 toward the sensor IC 500 in the thickness direction z inFIG. 26. The right end of the projecting portion 309 in FIG. 26 isdelimited by the upright surface 307.

In this embodiment, the sloped surface 303 is shorter than that of theimage sensor module 104, and hence providing the sloped surfaceanti-reflection portion 365 is scarcely necessary. Accordingly, thelight shielding member 360 according to this embodiment is onlyconstituted of the top face cover portion 364.

With the mentioned configuration, the support member 300 can be easilypositioned by fitting the projecting portion 309 in the groove 716.

In this embodiment, further, even though stray light should proceed inthe secondary scanning direction y along the lower face of the lens unit400, such stray light is incident on the upright surface 307 instead ofbeing reflected by the sloped surface 303, as in the support member 300shown in FIG. 24. Therefore, the stray light is less likely to bereflected toward the sensor IC 500, compared with the case where thestray light is incident on the sloped surface 303.

With the configuration according to this embodiment, the support member300 is only supported by the support surface 713, and not by the supportsurface 714. Such a configuration is particularly effective in the casewhere, for example, the housing 700 is composed of two parts that can besplit to left and right in FIG. 26. In the case where the housing 700 iscomposed of two separable parts, the parts may be distorted in differentmanners, which makes it difficult to accurately position the supportmember 300 with respect to both of the parts. However, with theconfiguration according to this embodiment it suffices that the supportmember 300 is accurately positioned with respect to one of the partsthat includes the support surface 713, and therefore the manufacturingprocess can be simplified.

The provision of the upright surfaces 306, 307 on the support member 300may be applied to similar fields, without limitation to the image sensormodule. In an LED printing head for example, normal printing performanceis disturbed when stray light emerges in a light guide that guides thelight from the LED. Forming the upright surface on the light guide isuseful for preventing such a situation.

FIGS. 27 and 28 illustrate an image sensor module according to a seventhembodiment of the present invention. The image sensor module 104 shownin FIGS. 27 and 28 may be incorporated, for example, in a documentscanner designed to optically read characters and images printed on theobject to be read 890 to thereby generate electronic data containingthose characters and images, as are the image sensor modules 101 to 106.While the substrate 600 is fitted in the recessed portion 720 of thehousing 700 in the image sensor modules 101 to 106, the substrate 600supporting the sensor IC 500 is fixed to the support member 300 in theimage sensor module 107. Except for such a difference in configuration,the basic structure of the image sensor module 107 is similar to that ofthe image sensor module 105. FIG. 28 is an enlarged cross-sectional viewof the support member 300, the lens unit 400, and the substrate 600shown in FIG. 27. Referring to FIGS. 27 and 28, the difference betweenthe image sensor module 107 and the image sensor module 105 will bedescribed hereunder.

As shown in FIG. 27, the housing 700 according to this embodiment doesnot have the recessed portion 720, and the substrate 600 is located inthe recessed portion 710.

The support member 300 according to this embodiment does not have thesloped surface 303 but instead includes the upright surface 307 erectedwith respect to the bottom face 301, as shown in FIG. 28. Since thesupport member 300 does not have the sloped surface 303, the lightshielding member 360 according to this embodiment is only constituted ofthe top face cover portion 364.

The support member 300 according to this embodiment further includes arecessed portion 300A formed so as to recede in the secondary scanningdirection y from the upright surface 307. The support member 300includes a recessed output surface 300A1 perpendicular to the secondaryscanning direction y and recessed sidewalls 300A2 erected with respectto the recessed output surface 300A1, and thus the recessed portion 300Ais composed of the recessed output surface 300A1 and the recessedsidewalls 300A2. The recessed output surface 300A1 has an elongaterectangular shape extending in the primary scanning direction x, and therecessed sidewalls 300A2 extend in the secondary scanning direction yfrom the respective sides of the recessed output surface 300A1. Thecross-section shown in FIG. 28 includes two end faces of the recessedsidewalls 300A2 extending from the respective longer sides of therecessed output surface 300A1.

The substrate 600 according to this embodiment is fixed to the uprightsurface 307, for example via a non-illustrated adhesive. The sensor IC500 according to this embodiment is mounted on the surface of thesubstrate 600 facing the upright surface 307, and is accommodated in therecessed portion 300A. A photodetecting surface 501 of the sensor IC 500is configured to face the recessed output surface 300A1. The surface ofthe substrate 600 opposite to the sensor IC 500 abuts against thesidewall 710 a of the recessed portion 710. Here, the substrate 600according to this embodiment corresponds to the sensor IC support basein the present invention.

In this embodiment, the light outputted from the output surface 402 ofthe lens unit 400 proceeds in the secondary scanning direction y and isoutputted through the recessed output surface 300A1 so as to proceed inthe secondary scanning direction y, and then is incident on thephotodetecting surface 501 of the sensor IC 500.

The image sensor module 107 according to this embodiment includes ananti-reflection member 370 provided in the recessed portion 300A. Theanti-reflection member 370 is formed so as to expose the recessed outputsurface 300A1 and to cover the recessed sidewalls 300A2. Theanti-reflection member 370 has, for example, a frame shape formed so asto surround the sensor IC 500, and is fitted in the recessed portion300A such that the outer periphery is in contact with the recessedsidewalls 300A2. The anti-reflection member 370 may be formed of a blackresin for example, and serves to prevent the light outputted from therecessed output surface 300A1 from being reflected by the recessedsidewalls 300A2, and to shield the light outputted from the recessedsidewalls 300A2. As described above, the light to be detected by thesensor IC 500 is the light proceeding from the lens unit 400 straightlyin the secondary scanning direction y. The light of a direction to bereflected by the recessed sidewalls 300A2, or the light outputtedthrough the recessed sidewalls 300A2 is stray light that should not beincident on the sensor IC 500. The anti-reflection member 370 isprovided in order to prevent such stray light from reaching the sensorIC 500.

In this embodiment also, the optical path arranged from the object to beread 890 to the sensor IC 500 is bent, and the section passing throughthe lens unit 400 is parallel to the secondary scanning direction y.Accordingly, prolonging the optical path does not incur an increase insize of the image sensor module 107 in the thickness direction z.Further, the support member 300 is formed of an acrylic resin and hencecan participate in securing a part of the rigidity of the housing 700.In this embodiment, the upright surface 306 in the vicinity of the leftend portion of the support member 300 in FIG. 27 abuts against the sideface 715 a of the elevated portion 715, and the substrate 600 fixed tothe upright surface 307 at the right end in FIG. 27 abuts against thesidewall 710 a, and thus the housing 700 is prevented from beingdistorted. Therefore, the image sensor module 107 can be made thinner inthe thickness direction z, without compromising the rigidity of thehousing 700.

In the image sensor module 107 according to this embodiment, since thesubstrate 600 is fixed to the support member 300 it is not mandatory toset the support member 300 accurately in position when placing thesupport member 300 in the housing 700. In the image sensor modules 101to 106, for example in the case where the support member 300 is fixed inan inclined posture, the light that has passed through the lens unit 400may fail to be incident on the sensor IC 500. However, with theconfiguration according to this embodiment, the substrate 600 is fixedto the support member 300 before being fixed to the housing 700. In casethat the light from the lens unit 400 fails to be incident on the sensorIC 500, such a defect can be detected before the support member 300 isplaced in the housing 700. Therefore, the configuration according tothis embodiment simplifies the process of setting the support member 300in the housing 700, thereby contributing to improving the productionyield by facilitating the manufacturing process and reducing the defectrate.

The anti-reflection member 370 is a frame-shaped member formed of aresin in this embodiment, however a black resin may be applied to therecessed sidewalls 300A2 so as to serve as the anti-reflection member370.

FIGS. 29 and 30 illustrate an image sensor module according to an eighthembodiment of the present invention. The image sensor module 106 shownin FIGS. 29 and 30 is different from the image sensor module 107 in theconfiguration of the support member 300 and the housing 700, and theremaining portions are configured in the same way as the image sensormodule 107.

The support member 300 according to this embodiment includes, as shownin FIG. 30, the sloped surface 303 inclined with respect to the bottomface 301 and the upright surface 307, and a projecting portion 309sticking out downward as illustrated from the bottom face 301. Toaccommodate the support member 300 thus configured, the housing 700according to this embodiment includes the groove 716 in which theprojecting portion 309 is fitted. The sloped surface 303 according tothis embodiment sloped surface 303 is configured in the same way as thesloped surface 303 of the support member 300 shown in FIG. 24.

The projecting portion 309 includes a lower surface 309 a parallel tothe bottom face 301, and the support member 300 according to thisembodiment is fixed to the lower surface 309 a via a non-illustratedadhesive. The recessed portion 300A according to this embodiment isformed so as to recede upward from the lower surface 309 a in thethickness direction z in FIG. 30. The recessed output surface 300A1according to this embodiment is parallel to the bottom face 301.Further, the upright surface 307 according to this embodiment connectsbetween the lower end of the sloped surface 303 and the right end of thelower surface 309 a in FIG. 30.

In this embodiment, the light from the output surface 402 of the lensunit 400 proceeds in the secondary scanning direction y and reflected bythe sloped surface 303 so as to proceed in the thickness direction z.The light reflected by the sloped surface 303 proceeds straightlydownward in the thickness direction z in FIG. 29, and is outputtedthrough the recessed output surface 300A1 toward the sensor IC 500.

In order to secure a sufficient optical path length of the lens unit 400in the configuration of the image sensor module 107, it is oftennecessary to increase the size of the image sensor module in thesecondary scanning direction y. However, in the image sensor module 108the light from the output surface 402 is reflected by the sloped surface303 in the thickness direction z, for example like the image sensormodule 105, and therefore the increase in size in the secondary scanningdirection y can be avoided.

FIGS. 31 and 32 illustrate an image sensor module according to a ninthembodiment of the present invention. The image sensor module 109 shownin FIGS. 31 and 32 may be incorporated, for example, in a documentscanner designed to optically read characters and images printed on theobject to be read 890 to thereby generate electronic data containingthose characters and images, as are the image sensor modules 101 to 108.In the image sensor modules 101 to 108 the support member 300 supportsthe lens unit 400, however the image sensor module 109 includes a lightguide or light guide member 380 in place of the support member 300 andthe lens unit 400. Except for such a difference in configuration, thebasic structure of the image sensor module 109 is similar to that of theimage sensor module 108. FIG. 32 is an enlarged cross-sectional view ofthe light guide member 380 shown in FIG. 31. Referring to FIGS. 31 and32, the difference between the image sensor module 109 and the imagesensor module 108 will be described hereunder.

The light guide member 380 is formed of a transparent acrylic resin, inan elongate bar shape extending in the primary scanning direction x. Thelight guide member 380 includes a bottom face 381 disposed in contactwith the housing 700, a sloped surface 382, a sloped surface 383, a topface 384, an upright surface 386, an upright surface 387, and aprojecting portion 389 sticking out downward from the bottom face 381 inthe thickness direction z in FIG. 32. The light guide member 380according to this embodiment is configured similarly to the supportmember 300 shown in FIG. 30. However, while the support member 300 is aconstituent for supporting the lens unit 400, the light guide member 380is configured so as to perform as the lens unit 400 does.

The bottom face 381 corresponds to the bottom face 301 of the supportmember 300. The bottom face 381 includes a pair of grooves 381 bcorresponding to the pair of grooves 301 b of the support member 300.The grooves 381 b each include a groove upright surface 381 bcorresponding to the groove upright surface 301 b 1 and a groove uprightsurface 381 b 2 corresponding to the groove sloped surface 301 b 2. Thebottom face 381 also includes a belt-like region 381 c corresponding tothe belt-like region 301 c, between the pair of grooves 381 b. Anon-illustrated adhesive for bonding the bottom face 381 and the supportsurface 713 together is introduced in the gap between the belt-likeregion 381 c and the support surface 713. The grooves 381 b serve toincrease the contact area between the bottom face 381 and the adhesive.Further, the groove upright surfaces 381 b 1 of the respective grooves381 b serve to prevent stray light from proceeding in the light guidemember 380 through an unintended route.

The sloped surface 382 corresponds to the sloped surface 302 of thesupport member 300, and the sloped surface 383 corresponds to the slopedsurface 303 of the support member 300. The top face 384 corresponds tothe top face 304 of the support member 300. While the support member 300shown in FIG. 30 includes the recessed portion 305 formed so as torecede from the top face 304 in the thickness direction z foraccommodating the lens unit 400, the light guide member 380 does nothave a recessed portion. The light guide member 380 includes an entranceportion 384 a located at the left end of the top face 384 in FIG. 32, soas to oppose the object to be read 890. The entrance portion 384 aincludes an entrance lens surface 391. The sloped surface 382 serves asa reflection surface that reflects the light from the entrance portion384 a in the secondary scanning direction y, and the sloped surface 383serves as an additional reflection surface spaced from the slopedsurface 382 in the secondary scanning direction y. The sloped surface383 reflects the light proceeding in the secondary scanning direction yso as to proceed in the thickness direction z.

The upright surface 386 corresponds to the upright surface 306 of thesupport member 300, and the upright surface 387 corresponds to theupright surface 307 of the support member 300. The upright surface 386and the upright surface 387 are perpendicularly erected with respect tothe bottom face 381. The upright surface 386 abuts against the side face715 a of the elevated portion 715 of the housing 700, and the uprightsurface 387 abuts against the sidewall 710 a of the recessed portion 710on the right in FIG. 31.

The projecting portion 389 corresponds to the projecting portion 309 ofthe support member 300. The substrate 600 is fixed to a lower surface389 a of the projecting portion 389 in the thickness direction z in FIG.32, via a non-illustrated adhesive. The light guide member 380 includesa recessed portion 380A formed so as to recede upward from the lowersurface 389 a of the projecting portion 389 in the thickness direction zin FIG. 32. The recessed portion 380A corresponds to the recessedportion 300A of the support member 300. The light guide member 380includes a recessed output surface 380A1 perpendicular to the thicknessdirection z and recessed sidewalls 380A2 erected with respect to therecessed portion output surface 380A1, and thus the recessed portion380A is composed of the recessed portion output surface 380A1 and therecessed sidewalls 380A2. The recessed output surface 380A1 correspondsto the recessed output surface 300A1 of the support member 300, and therecessed sidewalls 380A2 correspond to the recessed sidewalls 300A2 ofthe support member 300.

The recessed output surface 380A1 is spaced from the entrance portion384 a in the secondary scanning direction y, and corresponds to theoutput portion in the present invention. The recessed output surface380A1 includes an output lens surface 392. The substrate 600 supportsthe sensor IC 500, which is accommodated in the recessed portion 380A.The sensor IC 500 receives the light from the output lens surface 392.Further, the anti-reflection member 370 similar to that of the supportmember 300 is provided in the recessed portion 380A.

In the image sensor module 109 according to this embodiment, theentrance lens surface 391 and the output lens surface 392 serve as thelens unit 400 in the image sensor module 108. The optical path betweenthe entrance lens surface 391 and the output lens surface 392 is bent bythe sloped surface 382 and the sloped surface 383, and includes asection parallel to the secondary scanning direction y. Accordingly,prolonging the optical path does not incur an increase in size of theimage sensor module 109 in the thickness direction z. Further, thesupport member 380 is formed of an acrylic resin and hence canparticipate in securing a part of the rigidity of the housing 700. Inthis embodiment, the upright surface 386 abuts against the side face 715a of the elevated portion 715, and the upright surface 387 abuts againstthe sidewall 710 a, and thus the housing 700 is prevented from beingdistorted. Therefore, the image sensor module 107 can be made thinner inthe thickness direction z, without compromising the rigidity of thehousing 700.

In this embodiment, the substrate 600 is fixed to the light guide member380. Accordingly, it is not mandatory to perform accurate positioningwhen placing the light guide member 380 in the housing 700. Further,with the configuration including the lens unit 400 and the supportmember 300, the lens unit 400 has to be accurately fixed to the supportmember 300. However, the process of such accurate positioning can beskipped by employing the light guide member 380. Therefore, theconfiguration according to this embodiment simplifies the process ofsetting the support member 300 in the housing 700, thereby contributingto improving the production yield by facilitating the manufacturingprocess and reducing the defect rate.

FIGS. 33 to 35 illustrate an image sensor module according to a tenthembodiment of the present invention. The image sensor module 110 shownin FIGS. 33 to 35 is different from the image sensor module 105 in theconfiguration of a part of the support member 300 and the housing 700.The remaining portions of the image sensor module 110 are configured inthe same way as those of the image sensor module 105.

The support member 300 according to this embodiment includes a recessedportion 305′ extending in the primary scanning direction x and recedingin the direction opposite to the sensor IC 500. As shown in FIGS. 34 and35, the recessed portion 305′ has a rectangular cross-section. Therecessed portion 305′ is formed over generally the entire length of thesupport member 300 in the primary scanning direction x. The recessedportion 305′ is disposed on the route of the light reflected by thesloped surface 303 and proceeding toward the sensor IC 500.

As shown in FIG. 34, the support member 300 according to this embodimentincludes a chamfered portion 307 a formed between the upright surface307 and the bottom face 301. The chamfered portion 307 a serves toprevent collision between the corner of the support member 300 and thecorner between the sidewall 710 a and the support surface 714 of therecessed portion 710. Forming the chamfered portion 307 a allows thesupport member 300 to be more smoothly fitted in the recessed portion710.

As described with reference to the image sensor module 101, the sensorIC 500 includes the plurality of photodetecting surfaces. In FIG. 34,the photodetecting surface is denoted by a reference numeral 501. Thephotodetecting surface 501 is oriented upward in FIG. 34, so as toreceive the light incident thereon from above.

The housing 700 according to this embodiment includes a slit 718 facingthe sensor IC 500 and a pair of wall portions 719 fitted in the recessedportion 305′. The wall portions 719 each extend in the primary scanningdirection x generally over the entire length of the housing 700. Asshown in FIG. 35, the wall portions 719 each include a side face 719 aperpendicular to the secondary scanning direction y. In this embodiment,the side face 719 a of each of the wall portions 719 abuts against thesidewall of the recessed portion 305′.

The slit 718 serves to allow the light reflected by the sloped surface303 and proceeding toward the photodetecting surface 501 of the sensorIC 500 to pass therethrough, and is formed so as to extend in theprimary scanning direction x generally over the entire length of thehousing 700. As shown in FIG. 35, the slit 718 includes a pair of slopedsurfaces 718 a, a pair of sloped surfaces 718 b, and a pair ofhorizontal surfaces 718 c. The sloped surfaces 718 a are inclined so asto be more distant from each other in the secondary scanning directiony, toward the sensor IC 500 in the thickness direction z. The slopedsurfaces 718 b are inclined so as to be closer to each other in thesecondary scanning direction y, toward the sensor IC 500 in thethickness direction z. The sloped surfaces 718 b are located atpositions more distant from the sensor IC 500 in the thickness directionz, than the sloped surfaces 718 a. Here, the sloped surfaces 718 brespectively correspond to the surfaces of the wall portions 719opposite to the side face 719 a.

The horizontal surface 718 c each extend in the primary scanningdirection x and are perpendicular to the thickness direction z. As shownin FIG. 35, the horizontal surface 718 c on the left is located betweenthe left one of the pair of sloped surfaces 718 a and the left one ofthe pair of sloped surfaces 718 b. The horizontal surface 718 c on theright in FIG. 35 is located between the right one of the pair of slopedsurfaces 718 a and the right one of the pair of sloped surfaces 718 b.

In this embodiment, as shown in FIG. 35, the clearance between the pairof sloped surfaces 718 a at the upper end in the thickness direction zis narrower than the clearance between the pair of sloped surfaces 718 bat the lower end in the thickness direction z. Therefore, the horizontalsurfaces 718 c are oriented upward in FIG. 35, as is the photodetectingsurface 501.

The housing 700 according to this embodiment may be manufactured bycombining two molds and introducing a resin therebetween. In this case,the slit 718 can be formed by making the protruding portion of each moldabut each other. To be more detailed, the protruding portion of one orthe molds has a shape that defines the pair of sloped surfaces 718 a,and the protruding portion of the other mold has a shape that definesthe pair of sloped surfaces 718 b. It is preferable to form the leadingend portion of the protruding portions of the respective molds indifferent width, because the protruding portions may be shifted fromeach other upon being made to abut each other. It is because the widthof the protruding portion of one of the molds is narrower than that ofthe protruding portion of the other mold, that the pair of horizontalsurfaces 718 c is formed.

In this embodiment, the pair of wall portions 719 of the housing 700 isfitted in the recessed portion 305′ of the support member 300 whenplacing the support member 300 in the housing 700. Accordingly, thesupport member 300 can be more easily and more accurately positionedwith respect to the housing 700. In particular, the slit 718 formedbetween the pair of wall portions 719 serves as the path for the lightpassing through the lens unit 400 to reach the sensor IC 500. Utilizingthe pair of wall portions 719 a for the positioning enables the supportmember 300 to be more accurately positioned with respect to the slit718.

In this embodiment, further, the slit 718 includes the pair of slopedsurfaces 718 b, which makes the lower end portion thereof narrower thanthe upper end portion in FIG. 35 through which the light enters. Becauseof such a configuration the slit 718 serves as a diaphragm that blocks apart of the light from the sloped surface 303, and contributes topreventing unnecessary light from reaching the sensor IC 500.

Still further, in this embodiment the side faces 719 a of the respectivewall portions 719 abut against the sidewall of the recessed portion305′, thus blocking the light proceeding toward the slit 718 through thesidewall of the recessed portion 305′. Accordingly, stray lightproceeding through inside of the support member 300 is restricted fromintruding into the slit 718.

FIG. 36 illustrates an image sensor module according to an eleventhembodiment of the present invention. The image sensor module 111 shownin FIG. 36 is different from the image sensor module 110 in theconfiguration of the slit 718, and the remaining portions are configuredin the same way as the image sensor module 110.

In this embodiment, as shown in FIG. 36, the clearance between the pairof sloped surfaces 718 a at the upper end in the thickness direction zis wider than the clearance between the pair of sloped surfaces 718 b atthe lower end in the thickness direction z, contrary to theconfiguration of the image sensor module 110. Therefore, the horizontalsurfaces 718 c according to this embodiment are configured to face thephotodetecting surface 501. The slit 718 of such a shape can be formedby two molds in which the widths of the protruding portions are invertedfrom those of the molds for the image sensor module 110.

FIG. 37 illustrates an image sensor module according to a twelfthembodiment of the present invention. The image sensor module 112 shownin FIG. 37 is different from the image sensor module 110 in theconfiguration of the vicinity of the slit 718, and the remainingportions are configured in the same way as the image sensor module 110.

As shown in FIG. 37, the housing 700 according to this embodimentincludes the slit 718 facing the sensor IC 500 and a pair of slopedsurfaces 718 d extending from the lower end of the slit 718 asillustrated. The sloped surfaces 718 d are inclined so as to be moredistant from each other toward a lower position in FIG. 37. The sensorIC 500 is accommodated in the space between the pair of sloped surfaces718 d.

The support member 300 according to this embodiment includes aprojecting portion 309′ protruding downward from the bottom face 301 inFIG. 37. The projecting portion 309′ is disposed on the route of thelight reflected by the sloped surface 303 and proceeding toward thesensor IC 500, and extending into the slit 718.

With the configuration according to this embodiment, the projectingportion 309′ is fitted in the slit 718 when the support member 300 is tobe placed in the housing 700, and therefore the support member 300 canbe more easily and more accurately positioned with respect to thehousing 700.

The image sensor module according to the present invention is in no waylimited to the foregoing embodiments. The specific configuration of theconstituents of the image sensor module according to the presentinvention may be modified in various manners. For example, although thelight source unit 200 is located inside the housing 700 and the Lensunit 400 is configured to form the image based on the reflected lightfrom the object to be read 890 on the sensor IC 500 in the foregoingembodiments, the image sensor module according to the present inventionis not limited to such a configuration. The light source unit may belocated on the opposite side of the lens unit and the sensor IC acrossthe object to be read 890, and the lens unit may form the image based onthe light transmitted through the object to be read 890 on the sensorIC.

In the foregoing embodiments, the sloped surfaces 312, 313 are locatedon the respective sides of the transmissive portion 310 in the secondaryscanning direction y, and the reflection surfaces 321, 331 are formedalong the sloped surface 312, 313, respectively. However, the presentinvention is not limited to such a configuration. For example, one ofthe sides of the transmissive portion 310 in the secondary scanningdirection y may be formed in an orientation perpendicular to thesecondary scanning direction y. In this case, the same effect as thatprovided by the reflection surfaces 321, 331 can be attained by, forexample, forming sloped surfaces of the same inclination as the slopedsurfaces 312, 313 on the housing 700 and providing the non-transmissivelayer on such sloped surfaces.

Although the sloped surface 302 serves as the reflection surface in theimage sensor modules 104 to 112, the reflection surface 321 in the imagesensor modules 101, 102 may be adopted.

Further, although the light shielding member 360 does not cover thebottom face 301 in the image sensor module 105, the light shieldingmember 360 may include the bottom face anti-reflection portion 362 andthe bottom face cover portion 363, as the examples shown in FIGS. 21 and22. Likewise, the bottom face anti-reflection portion 362 may beprovided in the image sensor modules 106 to 112. Still further, thebottom face anti-reflection portion 362 may be provided on the bottomface 381 of the light guide member 380, in the image sensor module 109.

LIST OF REFERENCE SIGNS

-   -   x Primary scanning direction    -   y Secondary scanning direction    -   z Thickness direction    -   101 to 112 Image sensor module    -   200 Light source unit    -   210 LED module    -   221, 222, 223 LED chip    -   224, 225 Zener diode    -   231, 232, 233 Surface substrate    -   234 Back substrate    -   235, 237 Surface substrate    -   236, 238 Back substrate    -   241, 242, 243, 244 Lead    -   251 Mounting portion    -   252, 253, 254 Wire bonding portion    -   255, 256, 257, 258 Terminal portion    -   261 Conductive layer    -   262 Dielectric layer    -   265 Wire    -   270 Resin package    -   271 Opening    -   272 Positioning hole    -   280 Light guide    -   281 Incidence surface    -   282 Reflection surface    -   283 Output surface    -   285 Reflector    -   286 Base portion    -   287 Semicylindrical portion    -   288 Projection    -   300 Support member    -   300A Recessed portion    -   300A1 Recessed output surface    -   300A2 Recessed sidewall    -   301 Bottom face    -   301 a Output portion    -   301 b Groove    -   301 b 1 Groove upright surface    -   301 b 2 Groove sloped surface    -   301 c Belt-like region    -   302 Sloped surface    -   302 a Reflection surface    -   303 Sloped surface    -   303 a Reflection surface    -   304 Top face    -   304 a Entrance portion    -   305, 305′ Recessed portion    -   305 a Recessed portion bottom face    -   305 b Elevated portion    -   305 b 1 Elevated portion upright surface    -   306, 307 Upright surface    -   307 a Sloped surface    -   308 Junction surface    -   309, 309′ Projecting portion    -   309 a Lower surface    -   310 Transmissive portion    -   311 Bottom face    -   312, 313 Sloped surface    -   314 Cavity    -   315 Hole    -   316 Recessed portion    -   320, 330 Non-transmissive layer    -   321, 331 Reflection surface    -   340, 350 Mold    -   341, 351 Recessed portion    -   342, 352 Support pin    -   360 Light shielding member    -   361 Sloped surface anti-reflection portion    -   362 Bottom face anti-reflection portion    -   363 Bottom face cover portion    -   364 Top face cover portion    -   365 Sloped surface anti-reflection portion    -   366 Junction surface cover portion    -   370 Anti-reflection member    -   380 Light guide member    -   380A Recessed portion    -   380A1 Recessed portion output surface    -   380A2 Recessed sidewall    -   381 Bottom face    -   381 b Groove    -   381 b 1 Groove upright surface    -   381 b 2 Groove sloped surface    -   381 c Belt-like region    -   382 Sloped surface    -   382 a Reflection surface    -   383 Sloped surface    -   383 a Reflection surface    -   384 Top face    -   384 a Entrance portion    -   386, 387 Upright surface    -   389 Projecting portion    -   389 a Lower surface    -   391 Entrance lens surface    -   392 Output lens surface    -   400 Lens unit    -   401 Incidence surface    -   402 Output surface    -   500 Sensor IC    -   501 Photodetecting surface    -   600 Substrate    -   700 Housing    -   710, 720 Recessed portion    -   711 Light source chamber    -   712 Support region    -   713, 714 Support surface    -   715 Elevated portion    -   716 Groove    -   717 Terminal slot    -   718 Slit    -   718 a, 718 b Sloped surface    -   718 c Horizontal surface    -   718 d Sloped surface    -   719 Wall portions    -   800 Transmission plate    -   810 Light shielding layer (Light shielding member)    -   890 Object to be read

1. An image sensor module comprising: a light source unit that emits alinear light beam elongate in a primary scanning direction to an objectto be read; a lens unit including an incidence surface and an outputsurface oriented opposite to each other, the lens unit being configuredto receive light from the object through the incidence surface andoutput the light through the output surface; a sensor IC that receivesthe light outputted from the output surface; a housing that holds thelight source unit and the lens unit; and a support member that supportsthe lens unit such that the incidence surface is located more distantfrom the sensor IC than the output surface in a secondary scanningdirection; wherein the support member includes a primary reflectionsurface that reflects the light from the object toward the incidencesurface.
 2. The image sensor module according to claim 1, wherein thereflection surface is located so as to overlap the lens unit as viewedin the secondary scanning direction.
 3. The image sensor moduleaccording to claim 2, wherein the lens unit is supported such that anoptical axis of the lens unit is aligned with the secondary scanningdirection.
 4. The image sensor module according to claim 3, wherein thesupport member includes a bottom face perpendicular to a thicknessdirection orthogonal to both of the primary scanning direction and thesecondary scanning direction, and the housing includes a support regionprovided with a support surface held in contact with the bottom face. 5.The image sensor module according to claim 4, wherein the support memberincludes: a transmissive portion provided with a primary sloped surfaceinclined so as to be closer to the light source unit in the secondaryscanning direction as proceeding away from the bottom face in thethickness direction; and a non-transmissive layer formed so as to coverthe sloped surface; and the reflection surface is located at aninterface between the transmissive portion and the non-transmissivelayer.
 6. The image sensor module according to claim 5, wherein thetransmissive portion is formed integrally with the lens unit so as tocover the lens unit.
 7. The image sensor module according to claim 6,wherein the housing includes an elevated portion protruding in thethickness direction from the support surface, and the elevated portionis in contact with the non-transmissive layer.
 8. The image sensormodule according to claim 6, wherein the support region includes agroove penetrating therethrough in the thickness direction, the groovebeing formed at a position overlapping the sensor IC as viewed in thethickness direction, and the support member includes an additionalreflection surface formed so as to overlap the sensor IC as viewed inthe thickness direction.
 9. The image sensor module according to claim8, wherein the transmissive portion includes: an additional slopedsurface formed opposite to the primary sloped surface in the secondaryscanning direction and inclined so as to be closer to the light sourceunit as proceeding away from the bottom face in the thickness direction;and an additional non-transmissive layer formed so as to cover theadditional sloped surface; and the additional reflection surface islocated at the interface between the additional sloped surface and theadditional non-transmissive layer.
 10. The image sensor module accordingto claim 1, wherein the housing has a thickness direction orthogonal toboth of the primary scanning direction and the secondary scanningdirection, the housing supporting the support member, the support memberincludes a bottom face held in contact with the housing and a primaryupright surface erected from the bottom face and extending in theprimary scanning direction, and the reflection surface is inclined withrespect to the upright surface.
 11. The image sensor module according toclaim 10, wherein the upright surface is in contact with the housing.12. The image sensor module according to claim 10, wherein the supportmember includes an additional upright surface erected from the bottomface and extending in the primary scanning direction, and the additionalupright surface is located opposite to the primary upright surfaceacross the lens unit in the secondary scanning direction.
 13. The imagesensor module according to claim 12, wherein the support member includesan additional reflection surface that reflects the light from the outputsurface, and the lens unit is located between the primary reflectionsurface and the additional reflection surface in the secondary scanningdirection.
 14. The image sensor module according to claim 1, furthercomprising a sensor IC support base supporting the sensor IC and fixedto the support member.
 15. The image sensor module according to claim14, wherein the support member includes a recessed portion in which thesensor IC is placed.
 16. The image sensor module according to claim 15,further comprising an anti-reflection member located inside the recessedportion.
 17. The image sensor module according to claim 1, wherein thesupport member includes a recessed portion extending in the primaryscanning direction and recessed away from the sensor IC, and the housingincludes a pair of wall portions extending in the primary scanningdirection and fitted in the recessed portion, and a slit formed betweenthe pair of wall portions and facing the sensor IC.
 18. The image sensormodule according to claim 17, wherein the slit includes a pair ofprimary sloped surfaces extending in the primary scanning direction andinclined so as to be more distant from each other in the secondaryscanning direction as proceeding toward the sensor IC in a thicknessdirection orthogonal to both of the primary scanning direction and thesecondary scanning direction.
 19. The image sensor module according toclaim 18, wherein the slit includes a pair of additional sloped surfacesextending in the primary scanning direction and inclined so as to becloser to each other in the secondary scanning direction as proceedingtoward the sensor IC in the thickness direction orthogonal to both ofthe primary scanning direction and the secondary scanning direction, andthe pair of additional sloped surfaces is located more distant from thesensor IC than the pair of primary sloped surfaces in the thicknessdirection.
 20. The image sensor module according to claim 19, whereinthe slit includes a pair of horizontal surfaces extending in the primaryscanning direction and perpendicular to the thickness direction, andeach of the horizontal surfaces is located between one of the pair ofprimary sloped surfaces and one of the pair of additional slopedsurfaces.
 21. The image sensor module according to claim 20, wherein thesensor IC includes a photodetecting surface perpendicular to thethickness direction, and the pair of horizontal surfaces is oriented ina same direction as the photodetecting surface.
 22. The image sensormodule according to claim 20, wherein the sensor IC includes aphotodetecting surface perpendicular to the thickness direction, and thepair of horizontal surfaces is configured to face the photodetectingsurface.
 23. The image sensor module according to claim 1, wherein thehousing includes a slit facing the sensor IC, and the support memberincludes a projecting portion extending into the slit.
 24. The imagesensor module according to claim 1, further comprising a light shieldingmember that covers the support member in a manner such that at least thereflection surface is exposed.
 25. The image sensor module according toclaim 24, wherein the housing has a thickness direction orthogonal toboth of the primary scanning direction and the secondary scanningdirection and supports the support member, the support member includes abottom face supported by the housing and a primary sloped surfaceinclined with respect to the bottom face, the light shielding memberincludes a sloped surface anti-reflection portion held in close contactwith a part of the sloped surface, and the reflection surface is aportion uncovered with the sloped surface anti-reflection portion of thesloped surface and an interface with air.
 26. The image sensor moduleaccording to claim 25, wherein the light shielding member includes abottom face anti-reflection portion held in close contact with thebottom face.
 27. The image sensor module according to claim 25, whereinthe support member includes a top face opposite to the bottom face inthe thickness direction, and the light shielding member includes a topface cover portion that covers the top face.
 28. The image sensor moduleaccording to claim 25, wherein the support member includes an additionalsloped surface inclined with respect to the bottom face, the lens unitis located between the primary sloped surface and the additional slopedsurface in the secondary scanning direction, and the light shieldingmember includes an additional sloped surface anti-reflection portiondisposed in close contact with a part of the additional sloped surface.29. An image sensor module comprising: a light source unit that emits alinear light beam elongate in a primary scanning direction to an objectto be read; a lens unit including an incidence surface and an outputsurface oriented opposite to each other and configured to receive lightfrom the object through the incidence surface and output the lightthrough the output surface; a sensor IC that receives the lightoutputted from the output surface; a housing that holds the light sourceunit and the lens unit; and a support member that supports the lens unitsuch that the incidence surface is located more distant from the sensorIC than the output surface in a secondary scanning direction, whereinthe support member includes a reflection surface that reflects the lightfrom the object toward the sensor IC.
 30. The image sensor moduleaccording to claim 29, wherein the reflection surface is located so asto overlap the lens unit as viewed in the secondary scanning direction.31. The image sensor module according to claim 30, wherein the lens unitis supported such that an optical axis of the lens unit is aligned withthe secondary scanning direction.
 32. The image sensor module accordingto claim 31, wherein the support member includes a bottom faceperpendicular to a thickness direction orthogonal to both of the primaryscanning direction and the secondary scanning direction, and the housingincludes a support region provided with a support surface held incontact with the bottom face.
 33. The image sensor module according toclaim 32, wherein the support region includes a groove penetratingtherethrough in the thickness direction, the groove being formed at aposition overlapping the sensor IC as viewed in the thickness direction,and the reflection surface is located so as to overlap the groove asviewed in the thickness direction.
 34. The image sensor module accordingto claim 33, wherein the support member includes a transmissive portionprovided with a primary sloped surface inclined so as to be closer tothe light source unit in the secondary scanning direction as proceedingaway from the bottom face in the thickness direction, and anon-transmissive layer formed so as to cover the sloped surface, and thereflection surface is located at an interface between the transmissiveportion and the non-transmissive layer.
 35. The image sensor moduleaccording to claim 34, wherein the transmissive portion is formedintegrally with the lens unit so as to cover the lens unit.
 36. Theimage sensor module according to claim 35, further comprising anadditional reflection surface that reflects the light from the objecttoward the incidence surface.
 37. The image sensor module according toclaim 36, wherein the transmissive portion includes: an additionalsloped surface formed opposite to the primary sloped surface in thesecondary scanning direction and inclined so as to be closer to thelight source unit as proceeding away from the bottom face in thethickness direction; and an additional non-transmissive layer formed soas to cover the additional sloped surface, and the additional reflectionsurface is located at the interface between the additional slopedsurface and the additional non-transmissive layer.
 38. The image sensormodule according to claim 37, wherein the housing includes an elevatedportion protruding in the thickness direction from the support surface,and the elevated portion is in contact with the additionalnon-transmissive layer.
 39. The image sensor module according to claim29, wherein the support member includes a recessed portion extending inthe primary scanning direction and recessed away from the sensor IC, andthe housing includes a pair of wall portions extending in the primaryscanning direction and fitted in the recessed portion, and a slit formedbetween the pair of wall portions and facing the sensor IC.
 40. Theimage sensor module according to claim 39, wherein the slit includes apair of primary sloped surfaces extending in the primary scanningdirection and inclined so as to be more distant from each other in thesecondary scanning direction as proceeding toward the sensor IC in thethickness direction orthogonal to both of the primary scanning directionand the secondary scanning direction.
 41. The image sensor moduleaccording to claim 40, wherein the slit includes a pair of additionalsloped surfaces extending in the primary scanning direction and inclinedso as to be closer to each other in the secondary scanning direction asproceeding toward the sensor IC in the thickness direction orthogonal toboth of the primary scanning direction and the secondary scanningdirection, and the pair of additional sloped surfaces is located moredistant from the sensor IC than the pair of primary sloped surfaces inthe thickness direction.
 42. The image sensor module according to claim41, wherein the slit includes a pair of horizontal surfaces extending inthe primary scanning direction and perpendicular to the thicknessdirection, and each of the horizontal surfaces is located between one ofthe pair of primary sloped surfaces and one of the pair of additionalsloped surfaces.
 43. The image sensor module according to claim 42,wherein the sensor IC includes a photodetecting surface perpendicular tothe thickness direction, and the pair of horizontal surfaces is orientedin a same direction as the photodetecting surface.
 44. The image sensormodule according to claim 42, wherein the sensor IC includes aphotodetecting surface perpendicular to the thickness direction, and thepair of horizontal surfaces is configured to face the photodetectingsurface.
 45. The image sensor module according to claim 29, wherein thehousing includes a slit facing the sensor IC, and the support memberincludes a projecting portion extending into the slit.
 46. The imagesensor module according to claim 1, wherein the support member includesa cavity elongate in the primary scanning direction, and the lens unitis fitted in the cavity.
 47. The image sensor module according to claim1, wherein the support member includes a recessed portion formed so asto recede in the thickness direction orthogonal to both of the primaryscanning direction and the secondary scanning direction, and the lensunit is fitted in the recessed portion.
 48. The image sensor moduleaccording to claim 1, further comprising a substrate on which the sensorIC is mounted, wherein the light source unit includes: an LED moduleprovided with at least one LED chip, at least one lead on which the LEDchip is mounted, and a resin package covering a part of the lead andincluding an opening through which the LED chip is exposed; and a lightguide elongate in the primary scanning direction as a whole andincluding an incidence surface facing the opening, a reflection surfacethat reflects light from the incidence surface, and an output surfacethat outputs the light from the reflection surface in a form of a linearlight beam elongate in the primary scanning direction, and the leadincludes a terminal portion sticking out through the resin package inthe thickness direction, extending from a position retracted in thesecondary scanning direction with respect to the opening.
 49. The imagesensor module according to claim 48, wherein the substrate and at leasta part of the light guide are deviated from each other as viewed in thesecondary scanning direction.
 50. An image sensor module comprising: alight source unit that emits a linear light beam elongate in a primaryscanning direction to an object to be read; a light guide memberincluding an entrance portion facing the object, a primary reflectionsurface that reflects light from the entrance portion, and an outputportion spaced from the entrance portion in a secondary scanningdirection; a sensor IC that receives the light from the object throughthe light guide member; and a housing that holds the light source unitand the light guide member; wherein the entrance portion includes anentrance lens surface, and the output portion includes an output lenssurface.
 51. The image sensor module according to claim 50, furthercomprising a substrate supporting the sensor IC and fixed to the lightguide member.
 52. The image sensor module according to claim 50, whereinthe light guide member includes an additional reflection surface spacedfrom the primary reflection surface in the secondary scanning direction.53. The image sensor module according to claim 29, wherein the supportmember includes a cavity elongate in the primary scanning direction, andthe lens unit is fitted in the cavity.
 54. The image sensor moduleaccording to claim 29, wherein the support member includes a recessedportion formed so as to recede in the thickness direction orthogonal toboth of the primary scanning direction and the secondary scanningdirection, and the lens unit is fitted in the recessed portion.
 55. Theimage sensor module according to claim 29, further comprising asubstrate on which the sensor IC is mounted, wherein the light sourceunit includes: an LED module provided with at least one LED chip, atleast one lead on which the LED chip is mounted, and a resin packagecovering a part of the lead and including an opening through which theLED chip is exposed; and a light guide elongate in the primary scanningdirection as a whole and including an incidence surface facing theopening, a reflection surface that reflects light from the incidencesurface, and an output surface that outputs the light from thereflection surface in a form of a linear light beam elongate in theprimary scanning direction, and the lead includes a terminal portionsticking out through the resin package in the thickness direction,extending from a position retracted in the secondary scanning directionwith respect to the opening.